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單項選擇題

We must（）that the experiment is controlled as rigidly as possible.

A.assure
B.secure
C.ensure
D.issue

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單項選擇題

Be careful,（）you'll fall down.

A.on the contrary
B.or rather
C.or else
D.as for

單項選擇題

（）the movie I would have finished my paper last Sunday.

A.In spite of
B.Butf or
C.Because of
D.As for

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