He studied very hard all the time because he didn’t want to in his studies.A. fall behindB

问题补充：

He studied very hard all the time because he didn’t want to in his studies.

A. fall behind

B. be left behind

C. left behind

D. Both A and B

答案：

A. fall behind

B. be left behind

C. left behind

(答案→)D. Both A and B

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