no electronic computers, they could have been no satellites rockets.
A. Had there been
B. If there were
C. Should there be
D. If there are
Never such a marvelous place as the Great Wall before I got there.
A. did I see
B. I had seen
C. I saw
D. had I seen
, Sam would have been able to pass the exam.
A. If he studies more
B. If he were studying to a greater degree
C. Studying more
D. Had he studies more
had he gone to sleep than the telephone rang once more.
As soon as
B. No sooner
C. Hardly
D. Scarcely
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