(单选题)19: I suggested there ____ be a kind of language all could understand and use ____ . A: can; it B: /; / C: would; it D: may; / ...

(单选题)22: I don’t know why he is late.　　Nor do I. He _____ an accident. A: could have had B: should have had C: might have had D: must have had ...

(单选题)20: _____ the rain stops, we' ll set off for the station. A: Before B: Unless C: As soon as D: Though ...

(单选题)2: It is pretty well understood _________ controls the flow of carbon dioxide in and out the atmosphere today. A: that B: when C: what D: how ...

(单选题)21: The engineer ______my father works is about 50 years old. A: to whom B: on whom C: with which D: with whom ...

(单选题)3: _______ in this way，the situation doesn't seem so disappointing. A: To look at B: Looking at C: Looked at D: To be looked at ...

(单选题)10: I _________to help you but couldn’t get here in time. A: want B: had wanted C: have wanted D: was wanting ...

(单选题)6: By the end of this century, we_______ ours into a strong modern country. A: will build B: had built C: have built D: will have built ...

(单选题)25: _______ in a recent science competition, the three students were awarded scholarships totaling $21,000. A: Judged the best B: To be judged the best C: Judging the best D: Having judged the best ...

(单选题)15: The little town has now  grown into a modern city,and is (  )  what it used to be. A: twicw the size to B: twice the size as C: twice the size of D: twice the size than ...