目标排出如下图所示的效果，第二页的代码从\clearpage那边开始，被我注释掉了...如果直接运行，第一页也跟着错乱了，所以求高人指点一下，第一页的右栏如何平衡➕第二页继续双栏排版？
谢谢了！
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\title{\textbf{\LARGE{数学专业英语期末翻译作业}}} %大括号里填写标题,textbf加粗
\author{\textbf{学院：\underline{应用数学学院}}\\ %\\表示换行
\textbf{班级：\underline{\ \ \, }}\\ %\表示空格,下quad同
\textbf{姓名：\underline{\quad \ \quad \ }}\\
\textbf{学号：\underline{\ \,}}\\ \\
\textbf{翻译页码：P237-238}
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\date{\today} % 自动生成日期
\usepackage{booktabs}%线条粗细
\begin{document}
\par\addtolength{\leftskip}{100pt}
{\small
\noindent This formula is more complicated than it needs to be. If we combine $C=C_{1}-2C_{2}$, and $5C_{3}$ into a single arbitrary constant $C=C_{1}-2C_{2}+5C_{3}$, the formulas simplifies to
\noindent 这个公式比实际情况还要复杂。如果我们把$C=C_{1}-2C_{2}$,和 $5C_{3}$合并到一个任意常数的式子$C=C_{1}-2C_{2}+5C_{3}$，这个公式可以被简化成
$$ y=\frac{x^3}{3}-x^2+5x+C$$
and $still$ gives all the possible antiderivatives there are. For this reason, we recommend that you go right to the final form even if you elect to integrate term-by-term. Write
\noindent 并且依然给所有可能的不定积分。基于这个原因，我们推荐你直接看最后的形式，即使你需要逐项的整合。写
$$\int(x^2-2x+5)dx=\int x^2dx-\int 2xdx+\int 5dx$$
$$=\frac{x^3}{3}-x^2+5x+C.$$
Find the simpliest antiderivative you can for each part and add the arbitary constant of integration at the end.
\noindent 为每个部分找出它最简形式的反导数，然后在最后取一个任意的正常数。}
$\hfill\color{red}{\blacksquare}$%打小黑格并右对齐
\par
\addtolength{\leftskip}{-100pt}
\noindent\hspace*{-0.3em}\rule[-1pt]{17.85cm}{0.04em}
\hspace*{-0.2em}\colorbox[rgb]{0,0.28,0.56}{\textcolor{white}{\Large{\textbf{EXERCISES}}}} \
\textcolor[rgb]{0.50,0.25,0.25}{\Large{\textbf{4.7}}}
\begin{multicols}{2}
\noindent{\color[rgb]{0,0.28,0.56}{\footnotesize\textbf{Finding Antiderivatives}}}\\
{\color[rgb]{0,0.28,0.56}{\footnotesize\textbf{寻找反导数}}}\\
{\scriptsize
In Exercises 1-16, find an antiderivative for each function. Do as many as you can mentally. Check your answer by differentiation.}\\
{\scriptsize 在练习1-16中，为每个函数寻找一个不定积分。在你的能力范围内尽可能寻找。并且通过微分法验证你的答案。
}
\begin{enumerate}[leftmargin=5mm]
\begin{multicols}{3}
{\footnotesize
\item [\bf1.]\textbf{a.} {\textbf{$y=2x$}}
\item [\bf2.]\textbf{a.} {\textbf{$y=2x$}}
\item [\bf3.]\textbf{a.} {\textbf{$y=2x$}}
\item [\bf4.]\textbf{a.} {\textbf{$y=2x$}}
\item [\bf5.]\textbf{a.} {\textbf{$y=2x$}}
\item [\bf6.]\textbf{a.} {\textbf{$y=2x$}}
\item [\bf7.]\textbf{a.} {\textbf{$y=2x$}}
\item [\bf8.]\textbf{a.} {\textbf{$y=2x$}}
\item [\bf9.]\textbf{a.} {\textbf{$y=2x$}}
\item [\bf10.]\textbf{a.} {\textbf{$y=2x$}}
\item [\bf11.]\textbf{a.} {\textbf{$y=2x$}}
\item [\bf12.]\textbf{a.} {\textbf{$y=2x$}}
\item [\bf13.]\textbf{a.} {\textbf{$y=2x$}}
\item [\bf14.]\textbf{a.} {\textbf{$y=2x$}}
\item [\bf15.]\textbf{a.} {\textbf{$y=2x$}}
\item [\bf16.]\textbf{a.} {\textbf{$y=2x$}}
%第二栏
\item [\bf b.] {\textbf{$y=2x$}}
\item [\bf b.] {\textbf{$y=2x$}}
\item [\bf b.] {\textbf{$y=2x$}}
\item [\bf b.] {\textbf{$y=2x$}}
\item [\bf b.] {\textbf{$y=2x$}}
\item [\bf b.] {\textbf{$y=2x$}}
\item [\bf b.] {\textbf{$y=2x$}}
\item [\bf b.] {\textbf{$y=2x$}}
\item [\bf b.] {\textbf{$y=2x$}}
\item [\bf b.] {\textbf{$y=2x$}}
\item [\bf b.] {\textbf{$y=2x$}}
\item [\bf b.] {\textbf{$y=2x$}}
\item [\bf b.] {\textbf{$y=2x$}}
\item [\bf b.] {\textbf{$y=2x$}}
\item [\bf b.] {\textbf{$y=2x$}}
\item [\bf b.] {\textbf{$y=2x$}}
%第三栏
\item [\bf c.] {\textbf{$y=2x$}}
\item [\bf c.] {\textbf{$y=2x$}}
\item [\bf c.] {\textbf{$y=2x$}}
\item [\bf c.] {\textbf{$y=2x$}}
\item [\bf c.] {\textbf{$y=2x$}}
\item [\bf c.] {\textbf{$y=2x$}}
\item [\bf c.] {\textbf{$y=2x$}}
\item [\bf c.] {\textbf{$y=2x$}}
\item [\bf c.] {\textbf{$y=2x$}}
\item [\bf c.] {\textbf{$y=2x$}}
\item [\bf c.] {\textbf{$y=2x$}}
\item [\bf c.] {\textbf{$y=2x$}}
\item [\bf c.] {\textbf{$y=2x$}}
\item [\bf c.] {\textbf{$y=2x$}}
\item [\bf c.] {\textbf{$y=2x$}}
\item [\bf c.] {\textbf{$y=2x$}}
}
\end{multicols}
\end{enumerate}
%\begin{hlist}3
% \hitem text \hitem text \hitem text
% \hitem text \hitem text \hitem text
% \hitem text \hitem text \hitem text
% \hitem text \hitem text \hitem text
%\end{hlist}
\noindent{\color[rgb]{0,0.28,0.56}{\footnotesize\textbf{Finding Indefinite Integrals}}}\\
{\color[rgb]{0,0.28,0.56}{\footnotesize\textbf{寻找反导数}}}\\
{\scriptsize
In Exercises 17-56, find the most general antiderivative or indefinite integral. You may need to try a solution and then adjust your guess. Check your answers by differentiation.\\
在练习17-56中，为每个函数寻找一个不定积分。在你的能力范围内尽可能寻找。并且通过微分法验证你的答案。}
\begin{itemize}[leftmargin=4.8mm]
\begin{multicols}{2}
\item [\bf17.]{\textbf{$\int (sin2x-csc^{2}x)dx$}}
\item [\bf19.]{\textbf{$\int \frac{1+cos4t}{2}dt$}}
\item [\bf21.]{\textbf{$\int 3x^{\sqrt{3}}dx$}}
\item [\bf23.]{\textbf{$\int (1+tan^{2}\theta )d\theta$}}
\item [\bf25.]{\textbf{$\int cot^{2}xdx$}}
\item [\bf27.]{\textbf{$\int cos\theta (tan\theta+sec \theta)d\theta$}}
\item [\bf29.]{\textbf{$\int (2cos2x-3sin3x)dx$}}
\item [\bf31.]{\textbf{$\int \frac{1-cos6t}{2}dt$}}
\item [\bf33.]{\textbf{$\int x^{\sqrt{2}-1}dx$}}
\item [\bf35.]{\textbf{$\int (2=tan^{2}\theta)d\theta$}}
\item [\bf37.]{\textbf{$\int (1-cot^{2}x)dx$}}
\item [\bf39.]{\textbf{$\int \frac{csc\theta}{csc\theta -sin\theta}$}}
\item [\bf41.]{\textbf{$\int (sin2x-csc^{2}x)dx$}}
\item [\bf43.]{\textbf{$\int (4secxtanx-2(secx)^2{2}dx$}}
\item [\bf18.]{\textbf{$\int 3x^{\sqrt{3}}dx$}}
\item [\bf20.]{\textbf{$\int (1+tan^{2}\theta )d\theta$}}
\item [\bf22.]{\textbf{$\int cot^{2}xdx$}}
\item [\bf24.]{\textbf{$\int cos\theta (tan\theta+sec \theta)d\theta$}}
\item [\bf26.]{\textbf{$\int (2cos2x-3sin3x)dx$}}
\item [\bf28.]{\textbf{$\int \frac{1-cos6t}{2}dt$}}
\item [\bf30.]{\textbf{$\int x^{\sqrt{2}-1}dx$}}
\item [\bf32.]{\textbf{$\int (2=tan^{2}\theta)d\theta$}}
\item [\bf34.]{\textbf{$\int (1-cot^{2}x)dx$}}
\item [\bf36.]{\textbf{$\int \frac{csc\theta}{csc\theta -sin\theta}$}}
\item [\bf38.]{\textbf{$\int (1-cot^{2}x)dx$}}
\item [\bf40.]{\textbf{$\int \frac{csc\theta}{csc\theta -sin\theta}$}}
\item [\bf42.]{\textbf{$\int \frac{csc\theta}{csc\theta -sin\theta}$}}
\end{multicols}
\end{itemize}
%\clearpage
%\begin{enumerate}[leftmargin=4.8mm]
% \item [\bf44.]\small{\textbf{$\int \frac{1}{2}(csc^{2}x-cscxcotx)dx$}}%上一页自动顺延下来的。
% \begin{multicols}{2}
% {\balance
% \item [\bf45.]\small{\textbf{$\int (sin2x-csc^{2}x)dx$}}
% \item [\bf47.]\small{\textbf{$\int \frac{1+cos4t}{2}dt$}}
% \item [\bf49.]\small{\textbf{$\int 3x^{\sqrt{3}}dx$}}
% \item [\bf51.]\small{\textbf{$\int (1+tan^{2}\theta )d\theta$}}
% \item [\bf53.]\small{\textbf{$\int cot^{2}xdx$}}
% \item [\bf55.]\small{\textbf{$\int cos\theta (tan\theta+sec \theta)d\theta$}}
% \item [\bf46.]\small{\textbf{$\int (2cos2x-3sin3x)dx$}}
% \item [\bf48.]\small{\textbf{$\int \frac{1-cos6t}{2}dt$}}
% \item [\bf50.]\small{\textbf{$\int x^{\sqrt{2}-1}dx$}}
% \item [\bf52.]\small{\textbf{$\int (2=tan^{2}\theta)d\theta$}}
% \item [\bf54.]\small{\textbf{$\int (1-cot^{2}x)dx$}}
% \item [\bf56.]\small{\textbf{$\int \frac{csc\theta}{csc\theta -sin\theta}$}}
% }
% \end{multicols}
%\end{enumerate}
\end{multicols}
\end{document}
