<!doctype html>
<head>
<style>
.box { border:1px solid black; padding:3px; margin:3px }
.nowrap { white-space: nowrap; }
.float { float: left; }
.box div { background-color:lime; height:40px; border:1px solid black }
</style>
<body>

<div class="box"><a>One <div></div> Two</a></div>

<div class="box"><a>One<br><div></div><br>Two</a></div>

<div class="box float"><a>One <div></div> Two</a></div>