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<h1>Sub element examples</h1>
<h2>Math Forumulas:</h2>
<p>The coordinate of the <var>i</var>th point is
(<var>x<sub><var>i</var></sub></var>, <var>y<sub><var>i</var></sub></var>).
<h2>Chemical Forumula:</h2>
<p>H<sub>2</sub>O</p>
<h2>Abbreviations:</h2>
<p>Their names are
<span lang="fr"><abbr>M<sup>lle</sup></abbr> Gwendoline</span> and
<span lang="fr"><abbr>M<sup>me</sup></abbr> Denise</span>.
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