There was so serious a matter that I had no choice but _________ the police.
| A．called in | B．calling on | C．call for | D．to call in |
She had a talent for paintings and art, but her parents recommended that she______ literature .
| A．study | B．studies | C．must study | D．would study |
We should have teamspirit but there are a few occasions_____members are uncertain of their roles.
| A．when | B．whose | C．why | D．which |
The guests will be shown around a lot of places_____few other visitors can go.
| A．what | B．which | C．where | D．when |
----I’m sorry, but making a telephone call is not allowed in the meeting-room.
----Oh, I_____that, Sorry, I don’t do that again.
| A．don’t know | B．didn’t know | C．won’t know | D．haven’t known |
One reason why_____plane is such a popular means of_____transport is that it is very fast and safe.
| A．the; / | B．a; the | C．a;/ | D．the; the |