Every time I pass by her house, she's always busydoingsomething.
每次我经过她家，总看到她在忙。
2
The UI thread processes these messages whenever your application isn't busydoingsomething else.
无论何时你的程序不忙于做其它事情时该U I线程就处理这些消息。
3
All of that may take a lot of time, but if you're busydoingsomething else and then the information appears ready to use, the application feels responsive.