“标记”这一术语来自印刷业，该行业的校对人员把格式代码或修正代码标在书页稿样上，然后这些稿样被送去排版。

The term "markup" came from the printing industry, where proofreaders marked formatting or correction codes on page proof that were then typeset.

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删除：把字母，数字，词句或段落删去。校对时，用“删除符号”作标记。

Delete: To take out letter, figure, word or passage. In proof reading, a symbol is used as the proofreader's mark.

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