------- What do you think of Harry, our new roommate?
-------- I am not sure, but he is always asking ______ questions.
| A．a great many of | B．a great many | C．a great number | D．a large amount of |
Don't scold him; even an experienced engineer _____ make such a mistake after all.
| A．must | B．can | C．should | D．dare |
A survey of the opinions of scientists _____ that three hours of outdoor exercise a week _____
good for our health.
| A．show; are | B．shows; is | C．show; is | D．shows; are |
It was last year _____ I visited the museum _____ you had visited.
| A．that; that | B．when, where | C．that; where | D．when; that |
______ when to leave, I could only stay at home, _____ nothing.
| A．Knowing not; done | B．Not knowing; doing |
| C．Having not known; done | D．Not having known; doing |
While building a tunnel through the mountain, _____.
| A．an underground lake was discovered |
| B．workers discovered an underground lake |
| C．there was an underground lake discovered |
| D．a lake was discovered underground |