答案1
\subsection
请尝试此代码。将from \makeatletter
to的重新定义放在\makeatother
序言中。
\documentclass[a4paper]{amsbook}
\usepackage{lipsum}
\makeatletter
\def\subsection{\@startsection{subsection}{2}%
\z@{.5\linespacing\@plus.7\linespacing}{-.5em}%
{\normalfont\bfseries}}
\makeatother
\begin{document}
\chapter{This is a chapter}
\section{This is a section}
\subsection{This is a subsection}
\lipsum[1-2]
\end{document}