<html><head><script type="text/javascript" src="/jquery/jquery.js"></script><script type="text/javascript">$(document).ready(function(){ $("button").click(function(){ $("<b> Hello World!</b>").appendTo("p"); });});</script></head><body><p>This is a paragraph.</p><p>This is another paragraph.</p><button>在每个 p 元素的结尾添加内容</button></body></html>