## 编译环境 操作系统 * [x ] Windows 7/8/10 * [ ] macOS * [ ] Linux `若需勾选，请把[ ]改成[x]` Tex发行版 * [2020 ] TexLive `年份` * [ ] MikTeX `版本号` * [ ] CTeX `若需勾选，请把[ ]改成[x]` ## 我的问题 源码如下： \documentclass{article} \usepackage[UTF8]{ctex} \begin{document} 中文 \end{document} log文件如下： This is XeTeX, Version 3.14159265-2.6-0.999992 (TeX Live 2020/W32TeX) (preloaded format=xelatex 2020.8.8) 12 AUG 2020 22:46 entering extended mode restricted \write18 enabled. %&-line parsing enabled. **test02.tex (./test02.tex LaTeX2e <2020-02-02> patch level 5 L3 programming layer <2020-03-06> (c:/texlive/2020/texmf-dist/tex/latex/base/article.cls Document Class: article 2019/12/20 v1.4l Standard LaTeX document class (c:/texlive/2020/texmf-dist/tex/latex/base/size10.clo File: size10.clo 2019/12/20 v1.4l Standard LaTeX file (size option) ) \c@part=\count163 \c@section=\count164 \c@subsection=\count165 \c@subsubsection=\count166 \c@paragraph=\count167 \c@subparagraph=\count168 \c@figure=\count169 \c@table=\count170 \abovecaptionskip=\skip47 \belowcaptionskip=\skip48 \bibindent=\dimen134 ) (c:/texlive/2020/texmf-dist/tex/latex/ctex/ctex.sty (c:/texlive/2020/texmf-dist/tex/latex/l3kernel/expl3.sty Package: expl3 2020-07-17 L3 programming layer (loader) ! Undefined control sequence. l.67 \bool _new:N \g__expl_reload_bool The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Missing $ inserted. $ l.67 \bool_ new:N \g__expl_reload_bool I've inserted a begin-math/end-math symbol since I think you left one out. Proceed, with fingers crossed. ! LaTeX Error: Missing \begin{document}. See the LaTeX manual or LaTeX Companion for explanation. Type H for immediate help. ... l.67 \bool_ new:N \g__expl_reload_bool You're in trouble here. Try typing to proceed. If that doesn't work, type X to quit. LaTeX Font Info: External font `cmex10' loaded for size (Font) <7> on input line 67. LaTeX Font Info: External font `cmex10' loaded for size (Font) <5> on input line 67. ! Undefined control sequence. l.67 \bool_new:N \g __expl_reload_bool The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Missing { inserted. _ l.67 \bool_new:N \g__ expl_reload_bool A left brace was mandatory here, so I've put one in. You might want to delete and/or insert some corrections so that I will find a matching right brace soon. (If you're confused by all this, try typing `I}' now.) ! Undefined control sequence. l.69 \tl _if_exist:NF \c__expl_def_ext_tl The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. LaTeX Warning: Command \c invalid in math mode on input line 69. ! Double subscript. l.69 \tl_if_exist:NF \c__ expl_def_ext_tl I treat `x_1_2' essentially like `x_1{}_2'. ! Undefined control sequence. l.70 { \tl _const:Nn \c__expl_def_ext_tl { def } } The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. LaTeX Warning: Command \c invalid in math mode on input line 70. ! Double subscript. l.70 { \tl_const:Nn \c__ expl_def_ext_tl { def } } I treat `x_1_2' essentially like `x_1{}_2'. ! Undefined control sequence. l.71 \cs _gset_protected:Npn \__kernel_sys_configuration_load:n #1 The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! You can't use `macro parameter character #' in math mode. l.71 ...d:Npn \__kernel_sys_configuration_load:n # 1 Sorry, but I'm not programmed to handle this case; I'll just pretend that you didn't ask for it. If you're in the wrong mode, you might be able to return to the right one by typing `I}' or `I$' or `I\par'. ! Undefined control sequence. l.74 \cs _undefine:c { ver@ #1 .def } The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! You can't use `macro parameter character #' in math mode. l.74 \cs_undefine:c { ver@ # 1 .def } Sorry, but I'm not programmed to handle this case; I'll just pretend that you didn't ask for it. If you're in the wrong mode, you might be able to return to the right one by typing `I}' or `I$' or `I\par'. ! Argument of \@onefilewithoptions has an extra }. \par l.78 } I've run across a `}' that doesn't seem to match anything. For example, `\def\a#1{...}' and `\a}' would produce this error. If you simply proceed now, the `\par' that I've just inserted will cause me to report a runaway argument that might be the root of the problem. But if your `}' was spurious, just type `2' and it will go away. Runaway argument? ] [ ] \c __expl_def_ext_tl \ExplSyntaxOn ! Paragraph ended before \@onefilewithoptions was complete. \par l.78 } I suspect you've forgotten a `}', causing me to apply this control sequence to too much text. How can we recover? My plan is to forget the whole thing and hope for the best. ! Missing $ inserted. $ l.78 } I've inserted a begin-math/end-math symbol since I think you left one out. Proceed, with fingers crossed. ! Missing } inserted. } l.78 } I've inserted something that you may have forgotten. (See the above.) With luck, this will get me unwedged. But if you really didn't forget anything, try typing `2' now; then my insertion and my current dilemma will both disappear. ! Missing } inserted. } l.78 } I've inserted something that you may have forgotten. (See the above.) With luck, this will get me unwedged. But if you really didn't forget anything, try typing `2' now; then my insertion and my current dilemma will both disappear. Missing character: There is no ̧ in font cmmi5! Missing character: There is no ̧ in font cmmi5! Overfull \hbox (196.71214pt too wide) in paragraph at lines 67--78 []$[]\OML/cmm/m/it/10 ew \OT1/cmr/m/n/10 : \OML/cmm/m/it/10 N[]$ [] ! Too many }'s. } l.78 } You've closed more groups than you opened. Such booboos are generally harmless, so keep going. ! Undefined control sequence. l.79 \cs _gset_protected:Npn \__kernel_sys_configuration_load_std:n #1 The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Missing $ inserted. $ l.79 \cs_ gset_protected:Npn \__kernel_sys_configuration_load_std:n #1 I've inserted a begin-math/end-math symbol since I think you left one out. Proceed, with fingers crossed. ! LaTeX Error: Missing \begin{document}. See the LaTeX manual or LaTeX Companion for explanation. Type H for immediate help. ... l.79 \cs_ gset_protected:Npn \__kernel_sys_configuration_load_std:n #1 You're in trouble here. Try typing to proceed. If that doesn't work, type X to quit. ! You can't use `macro parameter character #' in math mode. l.79 ...n \__kernel_sys_configuration_load_std:n # 1 Sorry, but I'm not programmed to handle this case; I'll just pretend that you didn't ask for it. If you're in the wrong mode, you might be able to return to the right one by typing `I}' or `I$' or `I\par'. ! Undefined control sequence. l.81 \cs _undefine:c { ver@ #1 .def } The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! You can't use `macro parameter character #' in math mode. l.81 \cs_undefine:c { ver@ # 1 .def } Sorry, but I'm not programmed to handle this case; I'll just pretend that you didn't ask for it. If you're in the wrong mode, you might be able to return to the right one by typing `I}' or `I$' or `I\par'. ! Argument of \@onefilewithoptions has an extra }. \par l.84 } I've run across a `}' that doesn't seem to match anything. For example, `\def\a#1{...}' and `\a}' would produce this error. If you simply proceed now, the `\par' that I've just inserted will cause me to report a runaway argument that might be the root of the problem. But if your `}' was spurious, just type `2' and it will go away. Runaway argument? ] [ ] \c __expl_def_ext_tl ! Paragraph ended before \@onefilewithoptions was complete. \par l.84 } I suspect you've forgotten a `}', causing me to apply this control sequence to too much text. How can we recover? My plan is to forget the whole thing and hope for the best. ! Missing $ inserted. $ l.84 } I've inserted a begin-math/end-math symbol since I think you left one out. Proceed, with fingers crossed. ! Missing } inserted. } l.84 } I've inserted something that you may have forgotten. (See the above.) With luck, this will get me unwedged. But if you really didn't forget anything, try typing `2' now; then my insertion and my current dilemma will both disappear. Overfull \hbox (20.03395pt too wide) in paragraph at lines 79--84 []$[]\OML/cmm/m/it/10 set[]rotected \OT1/cmr/m/n/10 : \OML/cmm/m/it/10 Npn[][]e rnel[]ys[]onfiguration[]oad[]td \OT1/cmr/m/n/10 : \OML/cmm/m/it/10 n\OT1/cmr/m/ n/10 1[]$ [] ! Too many }'s. } l.84 } You've closed more groups than you opened. Such booboos are generally harmless, so keep going. ! Undefined control sequence. l.85 \clist _if_exist:NF \l__expl_options_clist The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Missing $ inserted. $ l.85 \clist_ if_exist:NF \l__expl_options_clist I've inserted a begin-math/end-math symbol since I think you left one out. Proceed, with fingers crossed. ! LaTeX Error: Missing \begin{document}. See the LaTeX manual or LaTeX Companion for explanation. Type H for immediate help. ... l.85 \clist_ if_exist:NF \l__expl_options_clist You're in trouble here. Try typing to proceed. If that doesn't work, type X to quit. LaTeX Warning: Command \l invalid in math mode on input line 85. ! Missing { inserted. _ l.85 \clist_if_exist:NF \l__ expl_options_clist A left brace was mandatory here, so I've put one in. You might want to delete and/or insert some corrections so that I will find a matching right brace soon. (If you're confused by all this, try typing `I}' now.) ! Undefined control sequence. l.86 { \clist _new:N \l__expl_options_clist } The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. LaTeX Warning: Command \l invalid in math mode on input line 86. ! Missing { inserted. _ l.86 { \clist_new:N \l__ expl_options_clist } A left brace was mandatory here, so I've put one in. You might want to delete and/or insert some corrections so that I will find a matching right brace soon. (If you're confused by all this, try typing `I}' now.) ! Undefined control sequence. l.90 \keys _define:nn { sys } The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Double subscript. l.90 \keys_ define:nn { sys } I treat `x_1_2' essentially like `x_1{}_2'. ! Undefined control sequence. l.94 { \sys _load_backend:n {#1} } , The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! You can't use `macro parameter character #' in math mode. l.94 { \sys_load_backend:n {# 1} } , Sorry, but I'm not programmed to handle this case; I'll just pretend that you didn't ask for it. If you're in the wrong mode, you might be able to return to the right one by typing `I}' or `I$' or `I\par'. ! Undefined control sequence. l.97 \sys _load_debug: The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.98 \debug _on:n { check-declarations } The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! You can't use `macro parameter character #' in math mode. l.100 driver .meta:n = { backend = # 1 } , Sorry, but I'm not programmed to handle this case; I'll just pretend that you didn't ask for it. If you're in the wrong mode, you might be able to return to the right one by typing `I}' or `I$' or `I\par'. ! Undefined control sequence. l.102 \sys _load_debug: , The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.105 \sys _load_debug: The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.106 \debug _on:n { log-functions } The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.109 = \g __kernel_backend_header_bool , The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Missing { inserted. _ l.109 = \g__ kernel_backend_header_bool , A left brace was mandatory here, so I've put one in. You might want to delete and/or insert some corrections so that I will find a matching right brace soon. (If you're confused by all this, try typing `I}' now.) ! Undefined control sequence. l.113 \bool _gset_true:N \g__kernel_deprecation_undo_recent_bool The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.113 \bool_gset_true:N \g __kernel_deprecation_undo_recent_bool The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Missing { inserted. _ l.113 \bool_gset_true:N \g__ kernel_deprecation_undo_recent_bool A left brace was mandatory here, so I've put one in. You might want to delete and/or insert some corrections so that I will find a matching right brace soon. (If you're confused by all this, try typing `I}' now.) ! Undefined control sequence. l.114 \sys _load_deprecation: The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.117 \cs _if_exist:NF \@expl@sys@load@backend@@ The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.117 \cs_if_exist:NF \@expl@sys@load@backend@@ The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.119 \tl _put_left:Nn \document The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Missing } inserted. } l.119 \tl_put_left:Nn \document I've inserted something that you may have forgotten. (See the above.) With luck, this will get me unwedged. But if you really didn't forget anything, try typing `2' now; then my insertion and my current dilemma will both disappear. ! Missing } inserted. } l.119 \tl_put_left:Nn \document I've inserted something that you may have forgotten. (See the above.) With luck, this will get me unwedged. But if you really didn't forget anything, try typing `2' now; then my insertion and my current dilemma will both disappear. ! Missing } inserted. } l.119 \tl_put_left:Nn \document I've inserted something that you may have forgotten. (See the above.) With luck, this will get me unwedged. But if you really didn't forget anything, try typing `2' now; then my insertion and my current dilemma will both disappear. ! Missing } inserted. } l.119 \tl_put_left:Nn \document I've inserted something that you may have forgotten. (See the above.) With luck, this will get me unwedged. But if you really didn't forget anything, try typing `2' now; then my insertion and my current dilemma will both disappear. ! Missing } inserted. } l.119 \tl_put_left:Nn \document I've inserted something that you may have forgotten. (See the above.) With luck, this will get me unwedged. But if you really didn't forget anything, try typing `2' now; then my insertion and my current dilemma will both disappear. ! Missing $ inserted. $ l.119 \tl_put_left:Nn \document I've inserted something that you may have forgotten. (See the above.) With luck, this will get me unwedged. But if you really didn't forget anything, try typing `2' now; then my insertion and my current dilemma will both disappear. Missing character: There is no ł in font cmmi10! Missing character: There is no ł in font cmmi7! ! Extra \endgroup. \endgroup l.119 \tl_put_left:Nn \document Things are pretty mixed up, but I think the worst is over. (c:/texlive/2020/texmf-dist/tex/latex/l3backend/l3backend-xdvipdfmx.def File: l3backend-xdvipdfmx.def 2020-06-29 L3 backend support: xdvipdfmx \g__graphics_track_int=\count171 \l__pdf_internal_box=\box45 \g__pdf_backend_object_int=\count172 \g__pdf_backend_annotation_int=\count173 ) No file test02.aux. \openout1 = `test02.aux'. LaTeX Font Info: Checking defaults for OML/cmm/m/it on input line 119. LaTeX Font Info: ... okay on input line 119. LaTeX Font Info: Checking defaults for OMS/cmsy/m/n on input line 119. LaTeX Font Info: ... okay on input line 119. LaTeX Font Info: Checking defaults for OT1/cmr/m/n on input line 119. LaTeX Font Info: ... okay on input line 119. LaTeX Font Info: Checking defaults for T1/cmr/m/n on input line 119. LaTeX Font Info: ... okay on input line 119. LaTeX Font Info: Checking defaults for TS1/cmr/m/n on input line 119. LaTeX Font Info: Trying to load font information for TS1+cmr on input line 1 19. (c:/texlive/2020/texmf-dist/tex/latex/base/ts1cmr.fd File: ts1cmr.fd 2019/12/16 v2.5j Standard LaTeX font definitions ) LaTeX Font Info: ... okay on input line 119. LaTeX Font Info: Checking defaults for TU/lmr/m/n on input line 119. LaTeX Font Info: ... okay on input line 119. LaTeX Font Info: Checking defaults for OMX/cmex/m/n on input line 119. LaTeX Font Info: ... okay on input line 119. LaTeX Font Info: Checking defaults for U/cmr/m/n on input line 119. LaTeX Font Info: ... okay on input line 119. Overfull \hbox (1648.97568pt too wide) in paragraph at lines 85--119 []$[]\OML/cmm/m/it/10 f[]xist \OT1/cmr/m/n/10 : \OML/cmm/m/it/10 NF[]$ [] ! Missing } inserted. } l.121 \endgroup I've inserted something that you may have forgotten. (See the above.) With luck, this will get me unwedged. But if you really didn't forget anything, try typing `2' now; then my insertion and my current dilemma will both disappear. ! Extra \endgroup. \endgroup l.121 \endgroup Things are pretty mixed up, but I think the worst is over. ! Undefined control sequence. l.122 \@expl@sys@load@backend@@ The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Extra }, or forgotten \endgroup. l.124 } I've deleted a group-closing symbol because it seems to be spurious, as in `$x}$'. But perhaps the } is legitimate and you forgot something else, as in `\hbox{$x}'. In such cases the way to recover is to insert both the forgotten and the deleted material, e.g., by typing `I$}'. ! Extra }, or forgotten \endgroup. l.125 } I've deleted a group-closing symbol because it seems to be spurious, as in `$x}$'. But perhaps the } is legitimate and you forgot something else, as in `\hbox{$x}'. In such cases the way to recover is to insert both the forgotten and the deleted material, e.g., by typing `I$}'. ! Undefined control sequence. l.126 \cs _gset_protected:Npn \@expl@sys@load@backend@@ The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Missing $ inserted. $ l.126 \cs_ gset_protected:Npn \@expl@sys@load@backend@@ I've inserted a begin-math/end-math symbol since I think you left one out. Proceed, with fingers crossed. ! Undefined control sequence. l.126 ...t_protected:Npn \@expl@sys@load@backend@@ The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.128 \str _if_exist:NF \c_sys_backend_str The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. LaTeX Warning: Command \c invalid in math mode on input line 128. ! Undefined control sequence. l.129 { \sys _load_backend:n { } } The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.131 \keys _set:nV { sys } \l__expl_options_clist The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. LaTeX Warning: Command \l invalid in math mode on input line 131. ! Missing { inserted. _ l.131 \keys_set:nV { sys } \l__ expl_options_clist A left brace was mandatory here, so I've put one in. You might want to delete and/or insert some corrections so that I will find a matching right brace soon. (If you're confused by all this, try typing `I}' now.) ! Undefined control sequence. l.132 \str _if_exist:NF \c_sys_backend_str The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. LaTeX Warning: Command \c invalid in math mode on input line 132. ! Undefined control sequence. l.133 { \sys _load_backend:n { } } The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.134 \bool _if:NT \g__expl_reload_bool The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.134 \bool_if:NT \g __expl_reload_bool The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Missing { inserted. _ l.134 \bool_if:NT \g__ expl_reload_bool A left brace was mandatory here, so I've put one in. You might want to delete and/or insert some corrections so that I will find a matching right brace soon. (If you're confused by all this, try typing `I}' now.) ! Undefined control sequence. l.136 \cs _gset_eq:NN \__kernel_sys_configuration_load:n The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.139 \file _input_stop: The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.141 \cs _if_free:cTF { ver@expl3.sty } The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.143 \tex _everyjob:D \exp_after:wN The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.145 \tex _the:D \tex_everyjob:D The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.145 \tex_the:D \tex _everyjob:D The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.146 \sys _everyjob: The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.149 { \sys _everyjob: } The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.150 \reverse _if:N \if_cs_exist:N \s__expl_stop The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.153 \cs _if_exist:NF \@expl@push@filename@@ The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.153 \cs_if_exist:NF \@expl@push@filename@@ The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.155 \tl _put_left:Nn \@pushfilename { \@expl@push@filename@@ } The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! LaTeX Error: Can be used only in preamble. See the LaTeX manual or LaTeX Companion for explanation. Type H for immediate help. ... l.155 \tl_put_left:Nn \@pushfilename { \@expl@push@filename@@ } Your command was ignored. Type I to replace it with another command, or to continue without it. ! Undefined control sequence. l.155 ... \@pushfilename { \@expl@push@filename@@ } The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.156 \tl _put_right:Nn \@pushfilename { \@expl@push@filename@aux@@ } The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! LaTeX Error: Can be used only in preamble. See the LaTeX manual or LaTeX Companion for explanation. Type H for immediate help. ... l.156 \tl_put_right:Nn \@pushfilename { \@expl@push@filename@aux@@ } Your command was ignored. Type I to replace it with another command, or to continue without it. ! Undefined control sequence. l.156 ...pushfilename { \@expl@push@filename@aux@@ } The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.158 \cs _gset_protected:Npn \@expl@push@filename@@ The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.158 ...gset_protected:Npn \@expl@push@filename@@ The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.162 \tl _to_str:N \@currname . The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.163 \tl _to_str:N \@currext The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.165 \tl _put_left:Nx \l__expl_status_stack_tl The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. LaTeX Warning: Command \l invalid in math mode on input line 165. ! Missing { inserted. _ l.165 \tl_put_left:Nx \l__ expl_status_stack_tl A left brace was mandatory here, so I've put one in. You might want to delete and/or insert some corrections so that I will find a matching right brace soon. (If you're confused by all this, try typing `I}' now.) ! Undefined control sequence. l.167 \bool _if:NTF \l__kernel_expl_bool The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. LaTeX Warning: Command \l invalid in math mode on input line 167. ! Missing { inserted. _ l.167 \bool_if:NTF \l__ kernel_expl_bool A left brace was mandatory here, so I've put one in. You might want to delete and/or insert some corrections so that I will find a matching right brace soon. (If you're confused by all this, try typing `I}' now.) ! Undefined control sequence. l.173 \cs _gset_protected:Npn \@expl@push@filename@aux@@ #1#2#3 The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.173 ..._protected:Npn \@expl@push@filename@aux@@ #1#2#3 The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! You can't use `macro parameter character #' in math mode. l.173 ...rotected:Npn \@expl@push@filename@aux@@ # 1#2#3 Sorry, but I'm not programmed to handle this case; I'll just pretend that you didn't ask for it. If you're in the wrong mode, you might be able to return to the right one by typing `I}' or `I$' or `I\par'. ! You can't use `macro parameter character #' in math mode. l.173 ...tected:Npn \@expl@push@filename@aux@@ #1# 2#3 Sorry, but I'm not programmed to handle this case; I'll just pretend that you didn't ask for it. If you're in the wrong mode, you might be able to return to the right one by typing `I}' or `I$' or `I\par'. ! You can't use `macro parameter character #' in math mode. l.173 ...cted:Npn \@expl@push@filename@aux@@ #1#2# 3 Sorry, but I'm not programmed to handle this case; I'll just pretend that you didn't ask for it. If you're in the wrong mode, you might be able to return to the right one by typing `I}' or `I$' or `I\par'. ! Undefined control sequence. l.175 \str _gset:Nn \g_file_curr_name_str {#3} The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.175 \str_gset:Nn \g _file_curr_name_str {#3} The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! You can't use `macro parameter character #' in math mode. l.175 \str_gset:Nn \g_file_curr_name_str {# 3} Sorry, but I'm not programmed to handle this case; I'll just pretend that you didn't ask for it. If you're in the wrong mode, you might be able to return to the right one by typing `I}' or `I$' or `I\par'. ! You can't use `macro parameter character #' in math mode. l.176 # 1 #2 {#3} Sorry, but I'm not programmed to handle this case; I'll just pretend that you didn't ask for it. If you're in the wrong mode, you might be able to return to the right one by typing `I}' or `I$' or `I\par'. ! You can't use `macro parameter character #' in math mode. l.176 #1 # 2 {#3} Sorry, but I'm not programmed to handle this case; I'll just pretend that you didn't ask for it. If you're in the wrong mode, you might be able to return to the right one by typing `I}' or `I$' or `I\par'. ! You can't use `macro parameter character #' in math mode. l.176 #1 #2 {# 3} Sorry, but I'm not programmed to handle this case; I'll just pretend that you didn't ask for it. If you're in the wrong mode, you might be able to return to the right one by typing `I}' or `I$' or `I\par'. ! Undefined control sequence. l.178 \cs _if_exist:NF \@expl@pop@filename@@ The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.178 \cs_if_exist:NF \@expl@pop@filename@@ The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.180 \tl _put_right:Nn \@popfilename The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! LaTeX Error: Can be used only in preamble. See the LaTeX manual or LaTeX Companion for explanation. Type H for immediate help. ... l.180 \tl_put_right:Nn \@popfilename Your command was ignored. Type I to replace it with another command, or to continue without it. ! Undefined control sequence. l.181 { \@expl@pop@filename@@ } The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.183 \cs _gset_protected:Npn \@expl@pop@filename@@ The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.183 \cs_gset_protected:Npn \@expl@pop@filename@@ The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Undefined control sequence. l.186 \tl _if_empty:NTF \l__expl_status_stack_tl The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. LaTeX Warning: Command \l invalid in math mode on input line 186. ! Missing { inserted. _ l.186 \tl_if_empty:NTF \l__ expl_status_stack_tl A left brace was mandatory here, so I've put one in. You might want to delete and/or insert some corrections so that I will find a matching right brace soon. (If you're confused by all this, try typing `I}' now.) LaTeX Warning: Command \l invalid in math mode on input line 188. ! Missing { inserted. _ l.188 ...{ \exp_after:wN \__expl_status_pop:w \l__ expl_status_stack_tl \s__e... A left brace was mandatory here, so I've put one in. You might want to delete and/or insert some corrections so that I will find a matching right brace soon. (If you're confused by all this, try typing `I}' now.) ! Undefined control sequence. l.188 ..._status_pop:w \l__expl_status_stack_tl \s __expl_stop } The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Missing { inserted. _ l.188 ...tatus_pop:w \l__expl_status_stack_tl \s__ expl_stop } A left brace was mandatory here, so I've put one in. You might want to delete and/or insert some corrections so that I will find a matching right brace soon. (If you're confused by all this, try typing `I}' now.) ! Undefined control sequence. l.190 \cs _gset_protected:Npn \__expl_status_pop:w #1#2 \s__expl_stop The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Double subscript. l.190 \cs_ gset_protected:Npn \__expl_status_pop:w #1#2 \s__expl_stop I treat `x_1_2' essentially like `x_1{}_2'. ! You can't use `macro parameter character #' in math mode. l.190 ...gset_protected:Npn \__expl_status_pop:w # 1#2 \s__expl_stop Sorry, but I'm not programmed to handle this case; I'll just pretend that you didn't ask for it. If you're in the wrong mode, you might be able to return to the right one by typing `I}' or `I$' or `I\par'. ! You can't use `macro parameter character #' in math mode. l.190 ...et_protected:Npn \__expl_status_pop:w #1# 2 \s__expl_stop Sorry, but I'm not programmed to handle this case; I'll just pretend that you didn't ask for it. If you're in the wrong mode, you might be able to return to the right one by typing `I}' or `I$' or `I\par'. ! Undefined control sequence. l.190 ...rotected:Npn \__expl_status_pop:w #1#2 \s __expl_stop The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Missing { inserted. _ l.190 ...tected:Npn \__expl_status_pop:w #1#2 \s__ expl_stop A left brace was mandatory here, so I've put one in. You might want to delete and/or insert some corrections so that I will find a matching right brace soon. (If you're confused by all this, try typing `I}' now.) ! Undefined control sequence. l.192 \tl _set:Nn \l__expl_status_stack_tl {#2} The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. LaTeX Warning: Command \l invalid in math mode on input line 192. ! Missing { inserted. _ l.192 \tl_set:Nn \l__ expl_status_stack_tl {#2} A left brace was mandatory here, so I've put one in. You might want to delete and/or insert some corrections so that I will find a matching right brace soon. (If you're confused by all this, try typing `I}' now.) ! You can't use `macro parameter character #' in math mode. l.192 \tl_set:Nn \l__expl_status_stack_tl {# 2} Sorry, but I'm not programmed to handle this case; I'll just pretend that you didn't ask for it. If you're in the wrong mode, you might be able to return to the right one by typing `I}' or `I$' or `I\par'. ! You can't use `macro parameter character #' in math mode. l.193 \int_if_odd:nTF {# 1} Sorry, but I'm not programmed to handle this case; I'll just pretend that you didn't ask for it. If you're in the wrong mode, you might be able to return to the right one by typing `I}' or `I$' or `I\par'. ! Undefined control sequence. l.197 \tl _if_exist:NF \l__expl_status_stack_tl The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Double subscript. l.197 \tl_ if_exist:NF \l__expl_status_stack_tl I treat `x_1_2' essentially like `x_1{}_2'. LaTeX Warning: Command \l invalid in math mode on input line 197. ! Missing { inserted. _ l.197 \tl_if_exist:NF \l__ expl_status_stack_tl A left brace was mandatory here, so I've put one in. You might want to delete and/or insert some corrections so that I will find a matching right brace soon. (If you're confused by all this, try typing `I}' now.) ! Undefined control sequence. l.199 \tl _new:N \l__expl_status_stack_tl The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. LaTeX Warning: Command \l invalid in math mode on input line 199. ! Missing { inserted. _ l.199 \tl_new:N \l__ expl_status_stack_tl A left brace was mandatory here, so I've put one in. You might want to delete and/or insert some corrections so that I will find a matching right brace soon. (If you're confused by all this, try typing `I}' now.) ! Undefined control sequence. l.200 \tl _set:Nn \l__expl_status_stack_tl { 0 } The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. LaTeX Warning: Command \l invalid in math mode on input line 200. ! Missing { inserted. _ l.200 \tl_set:Nn \l__ expl_status_stack_tl { 0 } A left brace was mandatory here, so I've put one in. You might want to delete and/or insert some corrections so that I will find a matching right brace soon. (If you're confused by all this, try typing `I}' now.) ! Undefined control sequence. l.202 \cs _gset_eq:NN \__kernel_sys_configuration_load:n The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Double subscript. l.202 \cs_ gset_eq:NN \__kernel_sys_configuration_load:n I treat `x_1_2' essentially like `x_1{}_2'. ) ! LaTeX Error: Can be used only in preamble. See the LaTeX manual or LaTeX Companion for explanation. Type H for immediate help. ... l.29 \GetIdInfo $Id: ctex.dtx 76d4e94 2020-06-06 23:22:18 +0800 Qing Lee to replace it with another command, or to continue without it. LaTeX Warning: You have requested, on input line 29, version `' of \GenericError { }{LaTeX Error: Can be used o nly in preamble}{See the LaTeX manual or LaTeX Companion for explanation.}{Your command was ignored. Type I to replace it with another command, or to continue without it.} expl3, but only version `2020-07-17 L3 programming layer (loader) ' is available. ! LaTeX Error: Can be used only in preamble. See the LaTeX manual or LaTeX Companion for explanation. Type H for immediate help. ... l.29 \GetIdInfo $Id: ctex.dtx 76d4e94 2020-06-06 23:22:18 +0800 Qing Lee to replace it with another command, or to continue without it. ! LaTeX Error: Can be used only in preamble. See the LaTeX manual or LaTeX Companion for explanation. Type H for immediate help. ... l.29 \GetIdInfo $Id: ctex.dtx 76d4e94 2020-06-06 23:22:18 +0800 Qing Lee to replace it with another command, or to continue without it. ! LaTeX Error: Can be used only in preamble. See the LaTeX manual or LaTeX Companion for explanation. Type H for immediate help. ... l.32 ...ExplFileDate}{2.5.3}{\ExplFileDescription} Your command was ignored. Type I to replace it with another command, or to continue without it. ! LaTeX Error: Can be used only in preamble. See the LaTeX manual or LaTeX Companion for explanation. Type H for immediate help. ... l.41 \@ifpackageloaded { ctexsize } Your command was ignored. Type I to replace it with another command, or to continue without it. ! Package ctex Error: Package `ctexsize' can not be loaded with `ctex'. For immediate help type H . ... l.42 ... ctex } { subpackage-loaded } { ctexsize } } `ctexsize' is actually a part of `ctex'. It is not necessary to load it separately. ! Missing \endcsname inserted. \protect l.43 ...new_eq:cN { ver@ctexsize. \@pkgextension } \c__ctex_version_tl } The control sequence marked should not appear between \csname and \endcsname. ! LaTeX Error: Can be used only in preamble. See the LaTeX manual or LaTeX Companion for explanation. Type H for immediate help. ... l.43 ...new_eq:cN { ver@ctexsize. \@pkgextension } \c__ctex_version_tl } Your command was ignored. Type I to replace it with another command, or to continue without it. ! Extra \endcsname. \exp_args:Nc ...>\exp_after:wN #1\cs:w #2\cs_end: l.43 ...new_eq:cN { ver@ctexsize. \@pkgextension } \c__ctex_version_tl } I'm ignoring this, since I wasn't doing a \csname. ! LaTeX Error: Can be used only in preamble. See the LaTeX manual or LaTeX Companion for explanation. Type H for immediate help. ... l.44 \@ifpackageloaded { ctexheading } Your command was ignored. Type I to replace it with another command, or to continue without it. ! Package ctex Error: Package `ctexheading' can not be loaded with `ctex'. For immediate help type H . ... l.45 ...ex } { subpackage-loaded } { ctexheading } } `ctexheading' is actually a part of `ctex'. It is not necessary to load it separately. ! Missing \endcsname inserted. \protect l.46 ..._eq:cN { ver@ctexheading. \@pkgextension } \c__ctex_version_tl } The control sequence marked should not appear between \csname and \endcsname. ! LaTeX Error: Can be used only in preamble. See the LaTeX manual or LaTeX Companion for explanation. Type H for immediate help. ... l.46 ..._eq:cN { ver@ctexheading. \@pkgextension } \c__ctex_version_tl } Your command was ignored. Type I to replace it with another command, or to continue without it. ! Extra \endcsname. \exp_args:Nc ...>\exp_after:wN #1\cs:w #2\cs_end: l.46 ..._eq:cN { ver@ctexheading. \@pkgextension } \c__ctex_version_tl } I'm ignoring this, since I wasn't doing a \csname. ! LaTeX Error: Can be used only in preamble. See the LaTeX manual or LaTeX Companion for explanation. Type H for immediate help. ... l.47 \RequirePackage { xparse , l3keys2e } Your command was ignored. Type I to replace it with another command, or to continue without it. ! LaTeX Error: Can be used only in preamble. See the LaTeX manual or LaTeX Companion for explanation. Type H for immediate help. ... l.55 \@ifpackagelater { expl3 } { 2020/04/06 } { } (That makes 100 errors; please try again.) Here is how much of TeX's memory you used: 428 strings out of 481358 8406 string characters out of 5927882 246145 words of memory out of 5000000 17901 multiletter control sequences out of 15000+600000 532346 words of font info for 25 fonts, out of 8000000 for 9000 36 hyphenation exceptions out of 8191 34i,15n,33p,249b,144s stack positions out of 5000i,500n,10000p,200000b,80000s No pages of output.