She had three sons,all of whom became doctors.这里面的连词为什么用whom,从句中缺少主语,不是wo og

题目

She had three sons,all of whom became doctors.这里面的连词为什么用whom,从句中缺少主语,不是wo og
从句中缺少主语,不是应该用who么,如果是whom的话,它在句子中作什么cheng dem

答案

all of whom
这个就是主语.
连接词 whom 是做介词 of 的宾语.
这种形式,很常见.