1 . Sometimes policemen wear plain clothes to ________ ________ (执行) special work.

2 . They _________ the maths problem when I came in.

A．worked on	B．were working on
C．were working	D．were working for

3 . —Whose trousers are these?               
—________, I think.

A．They

B．Their

C．Theirs

D．Them

4 . Why ________ you ________ and talk about it on the phone? You will get on well with each other.

A．not, call him up

B．don’t, call up him

C．don’t, call him up

D．did, call he up

5 . ________ American people and British people speak the same language, their cultures are quite different.

A．Since

B．Although

C．If

D．Because

6 . —Which would you like, a cup of tea or a glass of milk?
—________, thanks. I think I’ll just have a glass of water.

A．None

B．Neither

C．Both

D．Either

7 . —How do you know the store wants shop assistants?
—It ________ many signs in the neighborhood.

A．put down

B．put on

C．put out

D．put up

8 . 总之，保护环境是我们的责任。
___________________, it’s our duty to protect the environment.

9 . 昨天Lisa扔掉了她最喜欢的玩具。
Lisa _______________________ her favorite toy yesterday.

10 . 为了给妈妈看病，他每天努力工作赚钱。
To treat his mum’s illness, he works hard to ____________________.