1. 选用方框中短语的适当形式填空。

at least   across from   according to   once a year   millions of

1. （1） —How often does your father go abroad?

   —.

3. （2） There is a big tree behind the house. It has been there for ten years.
5. （3） —Where is the biggest bookstore?

   —Oh, it's over there, the white building.

7. （4） They spent dollars in building the factory.
9. （5） the school rules, you cannot eat anything when you are in the classroom.