我有这个评论在我的文档里
\documentclass[aoas,preprint]{imsart}
\RequirePackage[OT1]{fontenc}
\RequirePackage{amsthm,amsmath}
\RequirePackage[numbers]{natbib}
\RequirePackage[colorlinks,citecolor=blue,urlcolor=blue]{hyperref}
\usepackage{tabularx}
\usepackage{float}
\usepackage{cite}
\arxiv{arXiv:0000.0000}
\startlocaldefs
\numberwithin{equation}{section}
\theoremstyle{plain}
\newtheorem{thm}{Theorem}[section]
\newtheorem{acknowledgement}[thm]{Acknowledgement}
\newtheorem{algorithm}[thm]{Algorithm}
\newtheorem{axiom}[thm]{Axiom}
\newtheorem{case}[thm]{Case}
\newtheorem{claim}[thm]{Claim}
\newtheorem{conclusion}[thm]{Conclusion}
\newtheorem{condition}[thm]{Condition}
\newtheorem{conjecture}[thm]{Conjecture}
\newtheorem{corollary}[thm]{Corollary}
\newtheorem{criterion}[thm]{Criterion}
\newtheorem{definition}[thm]{Definition}
\newtheorem{example}[thm]{Example}
\newtheorem{exercise}[thm]{Exercise}
\newtheorem{lem}[thm]{Lemma}
\newtheorem{notation}[thm]{Notation}
\newtheorem{problem}[thm]{Problem}
\newtheorem{proposition}[thm]{Proposition}
\newtheorem{remark}[thm]{Remark}
\newtheorem{solution}[thm]{Solution}
\newtheorem{summary}[thm]{Summary}
\endlocaldefs
为什么我的定理、引理等没有标题？
答案1
（评论太长，因此作为答案发布）
请澄清“为什么我的定理、引理和...没有标题”是什么意思。当然，如下例所示，定理类环境被赋予了“定理”和“致谢”等标签。
顺便说一句，你不应该同时加载natbib和cite包。加载其中一个，但不要同时加载。
\documentclass[aoas,preprint]{imsart} % defines the macros "\startlocaldefs" and "\endlocaldefs"
\usepackage[T1]{fontenc}
\usepackage{amsthm,amsmath}
\usepackage[numbers]{natbib}
\usepackage{tabularx}
\usepackage{float}
%%%\usepackage{cite} % don't load both 'natbib' and 'cite'
\arxiv{arXiv:0000.0000}
%\usepackage[colorlinks,allcolors=blue]{hyperref}
\startlocaldefs
\numberwithin{equation}{section}
\theoremstyle{plain}
\newtheorem{thm}{Theorem}[section]
\newtheorem{acknowledgement}[thm]{Acknowledgement}
\endlocaldefs
\begin{document}
\setcounter{section}{1} % just for this example
\begin{thm}[Trivial]
$1+1=2$.
\end{thm}
\begin{acknowledgement}[Effusive]
Many thanks to everyone.
\end{acknowledgement}
\end{document}