<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"
	"http://www.w3.org/TR/html401/strict.dtd">
<html>
<head>
<title>Test</title>

<style type="text/css">
.block { display: block }
.runin { display: run-in }
.inline { display: inline }

</style>
</head>

<body>
Case A:

<div class="block">
    <div class="runin">This should </div>
    <div class="inline">run in.</div>
</div>

Case B:

<div class="block">
    <div class="runin">This should </div>
    run in.
</div>

Case C:

<div class="block">
    <div class="runin">This should </div>
    <div class="block">run in.</div>
</div>

Case D:

<div class="block">
    <div class="runin">This should NOT</div>
    <div class="runin">run in.</div>
</div>

</body>
</html>