用<em></em>标签是斜体

用<strong></strong>是加粗 

相对来说<mark></mark>标签最好看。

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    <title>HTML高亮标签<mark></mark></title>
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    <h1 align="center">
        清平乐<sub>李白™</sub>
    </h1>
    <hr color="red" />
    <p align="center">云想<em>衣裳</em>花想容，</p>
    <p align="center">春风拂槛<strong>露华浓</strong>；</p>
    <p align="center">若非<mark>群玉</mark>山头见，</p>
    <p align="center">会向瑶台月下逢。</p>

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HTML高亮标签＜mark＞＜/mark＞_html