我想输入一些多项选择题。我有以下代码。问题是，在某些问题中，我需要将选项放在一行中并均匀分布，而在某些问题中，我需要将两个选项放在一行中并均匀分布。我该怎么做呢？我知道有一些与此相关的答案，但我试图从中找出如何更改此代码，但每次我都会收到错误，我不想使用完全不同的代码。如果我能够在此代码中做到这一点，那就太好了。
我在这里先向您的帮助表示感谢。
\documentclass{article}
%--------------------------------------------------------------------
%--------------------------------------------------------------------
\newcounter{choice}
\renewcommand\thechoice{($\alph{choice}$)}
\newcommand\choicelabel{\thechoice}
%--------------------------------------------------------------------------------
\newenvironment{choices}%
{\list{\choicelabel}%
{\usecounter{choice}\def\makelabel##1{\hss\llap{##1}}%
\settowidth{\leftmargin}{W.\hskip\labelsep\hskip 0 em}%
\def\choice{%
\item
} % choice
\labelwidth\leftmargin\advance\labelwidth-\labelsep
\topsep=0pt
\partopsep=0pt
}%
}%
{\endlist}
%--------------------------------------------------------------------------------
\def\CChoice{%
\choice
\addanswer{\theenumi}{\thechoice}%
}
\let\CChoice\CChoice
% \par % Uncomment this to have choices always start a new line
% \let\par\@empty
% If we're continuing the paragraph containing the question,
% then leave a bit of space before the first choice:
\ifvmode\else\enskip\fi
\ignorespaces
%
{}
\makeatother
\newbox\allanswers
\setbox\allanswers=\hbox{}
\newcommand{\addanswer}[2]{%
\global\setbox\allanswers=\hbox{\unhbox\allanswers \quad #1.~#2}%
}
\newcommand{\showanswers}{%
\vfill
\begin{center}
Answers
\end{center}
\unhbox\allanswers
}
%--------------------------------------------------------------------
\begin{document}
\begin{enumerate}
\item One of these things is not like the others; one of these things
is not the same. Which one doesn't belong?
\begin{choices}
\choice George
\choice Paul
\choice John
\CChoice Ringo
\end{choices}
\item What was the color of George Washinton's white horse?
\begin{choices}
\choice Green
\CChoice Yellow
\choice White
\choice Socrates
\end{choices}
\item What was the color of George Washinton's white horse?
\begin{choices}
\choice Green
\choice Yellow
\CChoice White
\choice Socrates
\end{choices}
\item One of these things is not like the others; one of these things
is not the same. Which one doesn't belong?
\begin{choices}
\choice George
\choice Paul
\choice John
\choice Ringo
\end{choices}
\item What was the color of George Washinton's white horse?
\begin{choices}
\choice Green
\choice Yellow
\choice White
\choice Socrates
\end{choices}
\end{enumerate}
\showanswers
\end{document}
答案1
从这问题：我们创建一个多列环境：
\makeatletter
\newenvironment{multichoices}[1][2]{%
\begin{multicols}{#1}}{%
\end{multicols}}
\makeatother
并在环境中使用它choices。MWE：
\documentclass{article}
\usepackage{multicol}
%--------------------------------------------------------------------
%--------------------------------------------------------------------
\newcounter{choice}
\renewcommand\thechoice{($\alph{choice}$)}
\newcommand\choicelabel{\thechoice}
%--------------------------------------------------------------------------------
\newenvironment{choices}%
{\list{\choicelabel}%
{\usecounter{choice}\def\makelabel##1{\hss\llap{##1}}%
\settowidth{\leftmargin}{W.\hskip\labelsep\hskip 0 em}%
\def\choice{%
\item
} % choice
\labelwidth\leftmargin\advance\labelwidth-\labelsep
\topsep=0pt
\partopsep=0pt
}%
}%
{\endlist}
%--------------------------------------------------------------------------------
\def\CChoice{%
\choice
\addanswer{\theenumi}{\thechoice}%
}
\let\CChoice\CChoice
% \par % Uncomment this to have choices always start a new line
% \let\par\@empty
% If we're continuing the paragraph containing the question,
% then leave a bit of space before the first choice:
\ifvmode\else\enskip\fi
\ignorespaces
%
{}
\makeatother
\newbox\allanswers
\setbox\allanswers=\hbox{}
\newcommand{\addanswer}[2]{%
\global\setbox\allanswers=\hbox{\unhbox\allanswers \quad #1.~#2}%
}
\newcommand{\showanswers}{%
\vfill
\begin{center}
Answers
\end{center}
\unhbox\allanswers
}
\makeatletter
\newenvironment{multichoices}[1][2]{%
\begin{multicols}{#1}}{%
\end{multicols}}
\makeatother
%--------------------------------------------------------------------
\begin{document}
\begin{enumerate}
\item One of these things is not like the others; one of these things
is not the same. Which one doesn't belong?
\begin{choices}
\begin{multichoices}[4]
\choice George
\choice Paul
\choice John
\CChoice Ringo
\end{multichoices}
\end{choices}
\item What was the color of George Washinton's white horse?
\begin{choices}
\begin{multichoices}[2]
\choice Green
\CChoice Yellow
\choice White
\choice Socrates
\end{multichoices}
\end{choices}
\end{enumerate}
\end{document}
顺便说一句：为什么不使用该exam课程？