你以前来过北京吗

　　Have you been to Beijing before?你以前来过北京吗?

　　Have you been to Beijing before?

　　你以前来过北京吗?

　　Yes, I have. Many times.

　　是的，来过。来过很多次。

　　Really. You must know it quite well.

　　是吗？你一定非常了解北京。

　　Well, this is my sixth visit, I think. I get to know it a little bit more each time.

　　哦，我想这是第六次来北京了。我一次比一次更了解它。

　　Six times! That’s a lot. It’s nearly your home city!

　　六次！不少啊。差不多成了你的家乡了！

　　如果问某人在过去是否做过某事，你可以说：Have you been to Beijing before? /你以前去过北京吗? ;

　　Have you seen the Great Wall? / 你见过

　　You must know it quite well. /你一定对它非常了解。当你非常确定某事时，你可以用下面这个表达法：

　　You must . . . / 你一定 . . . ；例如, 在某人忙碌了一天之后说:

　　You must be tired / 你一定累了。