---Where has Mary been? I haven't seen her all day?
---Oh,in order not to be disturbed, she spent the whole day __in the study, ___ her report.
| A．locking;preparing | B．locked; prepared |
| C．locked; preparing | D．locking; prepared |
Only when your identity has been checked __________.
| A．you are allowed in | B．you will be allowed in |
| C．will you allow in | D．will you be allowed in |
The old couple have been 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 |
Only after my friend came __________.
| A．did the computer repair | B．he repaired the computer |
| C．was the computer repaired | D．the computer was repaired |
I have been living in the United States for twenty years, but seldom __________ so lonely as now.
| A．have I felt | B．I had felt | C．I have felt | D．had I felt |
__________, his idea was accepted by all the people at the meeting.
| A．Strange as might it sound | B．As it might sound strange |
| C．As strange it might sound | D．Strange as it might sound |