我的 MWE：
\documentclass[]{aiaa-tc}
\begin{document}
\section{Introduction}
\subsection{First}
\subsection{Second}
\section{Conclusion}
\subsection{First}
\subsection{Second}
\section*{Appendices}
\setcounter{subsection}{0}
\subsection{First}
\subsubsection{First}
\subsubsection{Second}
\subsection{Second}
\subsubsection{First}
\subsubsection{Second}
\end{document}
结果：
然而我想要实现的是：
答案1
尝试这个已编辑
\documentclass[]{aiaa-tc}
\makeatletter
\renewcommand\thesubsection {\thesection.\@Alph\c@subsection}
\renewcommand\thesubsubsection{\thesubsection.\@arabic\c@subsubsection}
\makeatother
\begin{document}
\section{Introduction}
\subsection{First}
\subsection{Second}
\section{Conclusion}
\subsection{First}
\subsection{Second}
\section*{Appendices}
\setcounter{subsection}{0}
\makeatletter
\def\@seccntformat#1{\@ifundefined{#1@cntformat}%
{\csname the#1\endcsname\quad}%
{\csname #1@cntformat\endcsname}%
}
\renewcommand\thesubsection {\@Alph\c@subsection}
\def\subsection@cntformat{\appendixname{} \thesubsection.\quad}
\makeatother
\subsection{First}
\subsubsection{First}
\subsubsection{Second}
\subsection{Second}
\subsubsection{First}
\subsubsection{Second}
\end{document}