如何制作一个div在里面包装两个浮动div ?

I don't know if it's a common problem, but I can't find the solution in web so far. I would like to have two divs wrapped inside another div, however these two divs inside have to be align the same level (for example: left one takes 20%width of the wrappedDiv, right one take another 80%). To achieve this purpose, I used the following example CSS. However, now the wrap DIV didn't wrap those divs all. The wrap Div has a small height than those two divs contained inside. How could I make sure that the wrap Div has the largest height as the contained divs? Thanks!!!I don't know if it's a common problem, but I ca