1
<h1 align="center">这是标题 1</h1>2
<h2 align="left">这是标题 2</h2>3
<h3 align="right">这是标题 3</h3>4
<h4 align="justify">这是标题 4</h4>
<h1 align="center">这是标题 1</h1><h2 align="left">这是标题 2</h2><h3 align="right">这是标题 3</h3><h4 align="justify">这是标题 4</h4>