the knowledge began to be accumulated according to a systematic plan

问题描述:

the knowledge began to be accumulated according to a systematic plan
请问这句话 为什么accumilated 不用ing形式

这句话中,关键动词搭配是:begin to do sth由于句子意思表达需要,knowledge和【积累accumulate】是【被动关系】,因此,gegin后面的搭配就变成了所给的 began【 to be accumulated不定式的被动式】.被动结构中,应该用...