15．Maria has to baby-sit． That's ____she can't come out with us.

A．why

B．how

C． when

D． what

14．A terrible thought suddenly____ me----had anyone broken into the house?

A．struck

B．beat

C．knocked

D． attacked

13．I had to ____because someone else wanted to use the phone.

A．give up

B． put up

C． hang up

D． ring up

12．----What are you going to do this afternoon?

----I'll probably go for a walk later on ____it stays fine.

A．as far as

B． so long as

C． even if

D． as if

11．---- You must phone us every week.

----Yes , I____.

A．must

B．have to

C．will

D．should

10．----Was Tom there when you arrived?

----Yes, but he ____home soon afterwards.

A．had gone

B．has gone

C．is going

D． went

9．----John took a photograph of you just now.

---- Really? What a pity! I ____.

A．didn't look

B．wasn't looking

C．hadn't looked

D．haven't looked

8．They are good friends .____is no wonder that they know each other so well.

A．This

B．That

C．There

D．It

7．----Are you familiar with the music?

----Yes. There was a time____ this kind of music was quite popular.

A．that

B．when

C．with which

D．about which

6．Paris is____ most beautiful city, where you can see ____ famous Eiffel Tower.

A．a; the

B．a; 不填

C．the; a

D．不填;the