题目内容

Research ______all over the world into the possible cause of cancer in the pastyears.

A. was made
B. had been made
C. has been making
D. has been made

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When you ________， I know for certain that you will feel much better.

A. are waking up
B. have been waking up
C. wake up
D. have woke

Hardly had Tom______ when the movie began.

A. seated
B. been been sat
C. sited
D. been seated

-----the ground is wet.-----Yes， didn't you know? ________for the last 20 minutes.

A. It's raining
B. It was raining
C. It's been raining

Johnson _____a novel about ancient China last year, but I don't know whetherhe has finished it.

A. has wrote
B. wrote
C. has written
D. was writing