It’s not easy for him _____ the work.
A. finish
B. to finish
C. finishing
D. finished
I knocked on the door but ________ answered.
A. somebody
B. anybody
C. nobody
D. everybody
Last year Polly ____ an English club last year and has improved her English a lot.
A. left
B. saw
C. joined
D. heard
A number of sheep ______ seen by us when we passed the field.
A. is
B. are
C. was
D. were
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