Every year a flood of farmers arrive in Shenzhen for the money-making jobs they ________ before leaving their hometowns.A.promised B.were promised C.have promised D.have been promised请帮忙分析一下句子成分,“before leaving their hometowns”是省略句吗?是怎么省略的.
问题描述：
Every year a flood of farmers arrive in Shenzhen for the money-making jobs they ________ before leaving their hometowns.
A.promised B.were promised C.have promised D.have been promised
请帮忙分析一下句子成分,“before leaving their hometowns”是省略句吗?是怎么省略的.
答
D
具体解释不来，就是被动语态
答
应该选D。简化这个句子就是Every year farmers arrive in Shenzhen for the jobs.they have been promised 是修饰jobs 的，农民工被许诺的，所以是被动语态，由于没有情景表示是过去发生的，故不选B. before leaving……不是省略，等同于before they leave
是第一次回答问题，没有经验，希望能让你明白。
答
B
农民工是被许诺的,是被动语态,动作在过去发生,用过去式,并且,before leaving their hometowns里的before是介系词,表示“在……之前”,介系词后面用的是动名词,希望我能帮助你解疑释惑.
答
D have been promised
before leaving their hometowns是个时间状语，因为句子主语就是这个动作的执行者，所以可以省略掉。