答案1
\documentclass{article}
\usepackage{amsmath}
\begin{document}
\begin{enumerate}
\item This looks good.
\item
$\begin{aligned}[t]
\mathrm{This} &= \mathrm{is} \\
&= \mathrm{not\ nicely\ aligned}
\end{aligned}$
\item \begin{tabular}[t]{ccc}
& Neither & is \\
this & table. & \\
\end{tabular}
\end{enumerate}
\end{document}