<html>
<body>

<table width="500px" cellspacing="0" cellpadding="0">
  <tr>
    <td style="background: lightgreen">This text should be on one line</td>
    <td style="width: 200px; background: yellow">Cell A</td>
  </tr>

  <tr>
    <td style="width: 100px; background: lightblue" colspan="2">Cell B</td>
  </tr>
</table>

</body>
</html>