Add United States to the list item and create an unordered list with a Neil Armstrong list item.

<html>
<body>
  Famous Astronauts
   <ul>
    <li>United States
     <ul>
      <li>Neil Armstrong</li>
     </ul>
    </li>
   </ul>
</body>
</html>]]>

Add United States to the list item. Then add the <ul> tag, the list item, and the </ul> tag.