1、It _____ Mike and Mary who helped the old man several days ago.

A、had been
B、was
C、were
D、are

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2、It was not until 1920 _____ regular radio broadcasts began.

A、when
B、that
C、since
D、which

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A、really
B、would
C、did
D、didn’t

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A、that
which
B、that
what
C、what
that
D、which
that

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A、it were
B、there was
C、it was
D、there were

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