He leaves Beijing on the 19th.
他19日离开北京。

A How long is your friend coming to Beijing for?
A 你的朋友将在北京呆多久？

B He arrives on the 9th. He’s coming for about ten days. He’s keen to see all the Olympic sites.
B 他9日到。他将呆10天左右。他很想看看所有的奥运场馆。

A Ten days is a good time to see lots of Beijing and do lots of things.
A 10天够看北京的很多地方，能做很多的事情。

B Yes, I’m sure it is. He’ll have a good time.
B 是的，我肯定。他将很开心。

A When does he go back to London?
A 他什么时候回伦敦？

B He leaves on the 19th.
B 他19日离开。

Notes 注释
1 Remember, if you ask about the length of time something will take, you can use How long . . . ? / How long . . . ? eg: How long is your friend coming for? / How long is your friend coming for? eg: How long have you been in Beijing? / How long have you been in Beijing?
记住，如果你问做某事所需的时间，你可以用How long . . . ? / 多久 . . . ?例如How long is your friend coming for? /你的朋友将呆多久？eg: How long have you been in Beijing? /你在北京多久了？
2 Remember the way you use numbers, especially when talking about dates (and the two ways you can write them, eg: 1st / first. eg: He leaves on the 19th (nineteenth) / He leaves on the 19th (nineteenth)
记住说数字的方法，尤其是当谈论日期的时候。有两种写法，例如1st / 1日。
He leaves on the 19th (nineteenth) /他19日离开。

Key phrases and sentences
How long is your friend coming to Beijing for?
He arrives on the 9th. 
He’s coming for about ten days.
He’s keen to see all the Olympic sites.
Ten days is a good time to see lots
of Beijing and do lots of things.
Yes, I’m sure it is. 
He’ll have a good time.
When does he go back to London?
He leaves on the 19th.

你的朋友将在北京呆多久？
他9日到。他将呆10天左右。
他很想看看所有的奥运场馆。
10天够看北京的很多地方，能做很多的事情。
是的，我肯定。
他将很开心。
他什么时候回伦敦？
他19日离开。