一Work hard, or you will_____ others．

一OK．I’ll try my best．

A．fall off           B．fall over               C．fall behind              D．fall down

1、C  考查动词短语。fall off“下降；跌落”；fall over“落在……之上；脸朝下跌倒”；fall behind“落在……的后面”；fall down“倒下”。结合题意可知C为正确答案。