I ______ swimming in the river and I always _____ to swim when I can.
A. am liking/have gone
B. am being liked/am going
C. like/go
D. have liked/have been going
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We have sometimes accidents on this line, but no accidents ______ since last winter.
A. occur
B. have occurred
C. have been occurring
D. are occurring
He _____ on this essay for twenty minutes but he _____ only a hundred words.
A. has been working/has written
B. is working/writes
C. has worked/has been writing
D. works/is writing
Elections _______ every four years and Congress meets once a year.
A. are taken place
B. are to be taken place
C. took place
D. take place
______ careless, or you will make mistakes.
A. Be not
B. Not be
C. Don’t
Don’t be
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