1 . It is their responsibility to________(sure) that the plans are carried out. (所给词的适当形式填空)

2 . __________is known to all that China is the biggest developing country in the world.

3 . I know the dinner with your boss will be boring, but if you get an important phone call during meal, it is easier to                                  .

A．make a hit

B．make an exit

C．make a difference

D．make a distinction

4 . — How did ________ feel to run 3,000 meters at the sports meeting?
—Terrible! Especially when I saw I was left so far ________ by others.

A．that; alone

B．it; alone

C．that; behind

D．it; behind

5 . _______ is known to us all that the old scientist, for _______ life was hard in the past, still works hard in his eighties.

A．As; whose

B．It; who

C．As; whom

D．It; whom

6 . _______ in the regulations that you shouldn’t tell other people the password of your e-mail account.

A．As is required	B．It is required
C．It requires	D．What is required

7 . It has been proved______eating vegetables in childhood helps to protect you against serious illnesses in later life.

A．if

B．because

C．when

D．that