I have a basic question, can I include HTML code in JS? (with `document.write`)

This is my HTML code:

```html
<li><a href="#" class="menulink">text</a></li>
<li><a href="#" class="menulink">text</a></li>
<li>
  <a href="#" class="menulink">text</a>
  <ul>
    <li>
      <a href="#" class="sub">text</a>
      <ul>
        <li class="topline"><a href="#">text</a></li>
        <li><a href="#">text</a></li>
        <li><a href="#">text</a></li>
        <li><a href="#">text</a></li>
        <li><a href="#">text</a></li>
        <li><a href="#">text</a></li>
        <li><a href="#">text</a></li>
      </ul>
    </li>
    <li>
      <a href="#" class="sub">text</a>
      <ul>
        <li class="topline"><a href="#">text</a></li>
        <li><a href="#">text</a></li>
      </ul>
    </li>

    <li>
      <a href="#" class="sub">text</a>
    </li>
    <li>
      <a href="#" class="sub">text</a>
    </li>
  </ul>
</li>

<li>
  <a href="#" class="menulink">text</a>
</li>
<li><a href="#" class="menulink">text</a></li>

```

And I want to include it in this JS code:

```js
window.onload = function () {
  document.getElementById("menu").innerHTML="";
}

```

Connect it by this code:

```
<p id="dropdown_menu"></p>

```

How can I do it?

*The full code is here* <http://jsfiddle.net/tsnave/eSgWj/4/>
thanks..