<!DOCTYPE html>
<style>
table {
  border-collapse: collapse;
}
td {
  border: 5px solid black;
  width: 100px;
  height: 100px;
}
</style>
Passes if there is a grid containing 2x2 squares.
<table>
  <tbody>
    <tr><td></td><td></td></tr>
    <tr><td></td><td></td></tr>
  </tbody>
</table>