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幼苗
共回答了17个问题采纳率:94.1% 举报
1.当从句动作发生在主句的过去动作之前时,用过去完成时.
He said that he had finished his homework.
2.在任何情况下助动词后都要用原形.
3.引号中的句子里不一定都要用原形,要看句子要表达的时态.
4.被动语态中必需的be的某种形式.你所说的应该是动词的非谓语形式.
如 the meeting held yesterday.(昨天开的会)
The meeting was held yesterday.(这个会是昨天开的)
前一个是过去分词修饰名词meeting作定语,属于非谓语形式而不属于句子.后一个是句子,所以才有完整的被动语态形式.
1年前
6