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<title></title>
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<script src="jquery-3.3.1.js"></script>
<script>
$(function () {
$('#btn').click(function () {
$('br').replaceWith('<hr color="yellow"/>');
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<input type="button" name="name" value="替换1" id="btn" /><br />
<input type="button" name="name" value="替换2" id="btn2" /><br />
静夜思<br />
床前明月光，<br />
疑是地上霜，<br />
举头望明月，<br />
低头思故乡。<br />
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