I'm a student.

我是学生。

Do you know any of those people?

你认识那些人吗？

While we were having breakfast,John was talking on the telephone.

当我们正在吃早餐时，约翰正在打电话。

Your niece is engaged,isn't she?

你的侄女订婚了，是吗？

I'd like to try on this sweater.

我想试穿这件毛衣。

They had to call in a heart specialist.

他不得不请一位心脏病专家。