I think you misunderstand what I mean by "compose".

You can compose most HTML elements including <select> easily:

    <label>
      What do you like?
      <select name="choice">
        <option value="first">First Value</option>
        <option value="second" selected>Second Value</option>
        <option value="third">Third Value</option>
      </select>
    </label>

There you go, you did composition. The logic between those elements, how doing something with one element affects the other element, that is a different matter.

For some elements it might be invalid HTML if one is inside the other. Like a <div> inside a <span> or so.