2. The boy was so careful that he ________ the street and broke his leg.

2. The boy was so careful that he ________ the street and broke his leg.
A. fell down B. fell over C. fell off D. fell onto
答案是C 为什么，其他的怎么错了

fall down 失败
fall over 摔倒
fall off
1. (数量)减少

Enrollment has fallen off this year.

今年入学人数减少了。

2. (势力、地位等)降低

3. 脱离
fall onto?摔到什么上?

你答案错误了吧 应该选fall over

固定搭配吧

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