左对齐是l
右对齐是r
居中是c
\begin{table} \centering \caption{\label{tab:widgets}Notation summary.} \begin{tabular}{l|l} ⬅就是这里控制每一列的对齐方式 Notation & Meaning \\\hline Widgets & 42 \\ Gadgets & 13 \end{tabular} \end{table}