\documentclass[10pt,a4paper,twoside]{article}
\usepackage[UTF8, fontset = none, heading = true]{ctex}
\setCJKmainfont[BoldFont=黑体,ItalicFont=楷体]{华文中宋}
\usepackage{amssymb,amsmath,amsfonts,amsthm,mathrsfs,graphicx}
\usepackage{ifthen,indentfirst,enumerate,color,lastpage}
\usepackage{tikz}
\usepackage{multicol}
\usepackage{multirow}
\usepackage{makecell}
\usepackage{longtable}
\usepackage{diagbox}
\usepackage{hyperref}
\usepackage{tcolorbox}
\usepackage[top=1in, bottom=1in,left=0.8in,right=0.8in]{geometry}
\usepackage{fancyhdr}
\fancyhf{}
\fancyhead[LO]{学号\blank{50} \ 姓名\blank{80}}
\chead{\papername}
\rhead{--\ \thepage\ of \pageref{LastPage} \ --}
\pagestyle{fancy}
\ctexset{section={
name={},
number=\chinese{section},
}}
\CTEXsetup[format={\bfseries\raggedright}]{section}
\usetikzlibrary{arrows,calc,intersections,patterns,decorations.pathreplacing,3d,angles,quotes,positioning,shapes.geometric}

\renewcommand{\baselinestretch}{1.5}
\newtheorem{defi}{定义~}
\newtheorem{eg}{例~}
\newtheorem{ex}{~}
\newtheorem{rem}{注~}
\newtheorem{thm}{定理~}
\newtheorem{coro}{推论~}
\newtheorem{axiom}{公理~}
\newtheorem{prop}{性质~}
\newcommand{\blank}[1]{\underline{\hbox to #1pt{}}}
\newcommand{\bracket}[1]{(\hbox to #1pt{})}
\newcommand{\onech}[4]{\par\begin{tabular}{p{.9\linewidth}}
A.~#1\\
B.~#2\\
C.~#3\\
D.~#4
\end{tabular}}
\newcommand{\twoch}[4]{\par\begin{tabular}{p{.46\linewidth}p{0\linewidth}p{.46\linewidth}p{0\linewidth}}
A.~#1& &B.~#2&\\
C.~#3& &D.~#4&
\end{tabular}}
\newcommand{\vartwoch}[4]{\par\begin{tabular}{p{.46\linewidth}p{.46\linewidth}}
(1)~#1& (2)~#2\\
(3)~#3& (4)~#4
\end{tabular}}
\newcommand{\fourch}[4]{\par\begin{tabular}{p{.23\linewidth}p{.23\linewidth}p{.23\linewidth}p{.23\linewidth}}
A.~#1 &B.~#2& C.~#3& D.~#4
\end{tabular}}
\newcommand{\varfourch}[4]{\par\begin{tabular}{p{.23\linewidth}p{.23\linewidth}p{.23\linewidth}p{.23\linewidth}}
(1)~#1 &(2)~#2& (3)~#3& (4)~#4
\end{tabular}}

\tcbuselibrary{breakable}
\newcommand{\papername}{<<待替换1>>}

\begin{document}
\begin{center}
{\bf\large \papername}
\end{center}

<<待替换2>>



\end{document}