My head-teacher helped me a lot when I was in trouble. I do wish I could do something for him__________ one day.
| A．in turn | B．in common | C．in return | D．in theory |
It is believed _______ he has gone to Shanghai. The problem is ________ we can’t get in touch with him.
| A．when; that | B．that; that | C．that; whether | D．不填；不填 |
____ the 1990s, the number of antelopes had fallen to about 50,000.
| A．During | B．Since | C．By | D．Over |
I'll never forget the day _______ I bought my own guitar with my own money.
| A．where | B．on which | C．on when | D．that |
--Are you sure to help me find____________ bed for my new house?
--Of course, but not now. I'm heading, for____________ bed and a good sleep.
| A．a, a | B．a, 不填 | C．the, a | D．a, the |
The old couple married for 40 years and never once____ with each other.
| A．they had quarreled. | B．they have quarreled |
| C．have they quarreled | D．had they quarreled. |