[ Tenses ]
He gave us warning to stay away from the machine while it __________.
A. had worked
B. was working
C. would work
D. would be working

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Vocabulary › Viewpersistent in effort; stubbornly
A. resemblance
B. imploringly
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Tenses › View
I ______ to New York three times this year.
A. have been
B. was
C. were
D. had been