m元素表示文本被“加上标志”，但是不一定要强调。

The m element indicates text that is "marked" somehow but not necessarily emphasized.

youdao

很多书写用字母(比如：法语)需要上标或下标才能正确展示。在这些情况下，SUB和SUP元素应该用来标记文本。

Many scripts (e. g., French) require superscripts or subscripts for proper rendering. The sub and sup elements should be used to markup text in these cases.

youdao

中间划线，上标，下标元素。

Strikethrough, subscript, and superscript elements.

youdao