如何在jquery中使用其他div更改div内容？

I have a problem about changing div content. My form has a selectbox for regions. The options are Philippines and United States. The logic is if the user select the Philippines. The textbox below the selecbox will be automatically replace by other div that has a selectbox also. And if the user select United States or no selection it will just display the textbox below. By default there's a textbox below the selection box. Here's my code.I have a problem about changing div content. My