问题

The scientists ________ on the new medicine fortwo years. They will succeed in no time.
A: work
B:are working
C:have worked
D:will work
B:are working
C:have worked
D:will work
正确答案是:
同类题型
What’s that— _____is a jacket.
nted all kinds of fruits on the hill,______ beaches, pears, apples and so on
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________ from his accent, he must be from Hunan.[ ]
These drawings are made by the three-year-old girls here.— Well, ______creative the children are!