答案1
像这样?
和tcolorbox
:
\documentclass{article}
\usepackage[many]{tcolorbox}
\newcounter{task}
\newtcolorbox{call out}%
{enhanced jigsaw,
breakable,
before skip=\baselineskip,
boxsep=0pt,
boxrule=0mm,
colback=white, colframe={red},
top=0mm,bottom=0mm,left=2mm,right=0mm,
arc=0mm,
leftrule=2mm,
}% end of task
\usepackage{lipsum}
\begin{document}
\lipsum[1-3]
\begin{call out}
\lipsum[4-6]
\end{call out}
\lipsum[7]
\end{document}