就这样讲英语。。。。。(32)

读完了Inversion in English Grammar英语语法的反转法，以下的句子，你有把握分辨那个是对是错？

1. Not once he complained about Allan.

2. Only if two parties sit down and talk, misunderstanding can be avoided.

3. Only when he screamed we realized that he was injured.

4. Only under special circumstances approval will be granted.

上面的句子开端都是用了限制性副词(restrictive adverbs)，正确的句子是

1. Not once did he complain about Allan.

2. Only if two parties sit down and talk, can misunderstanding be avoided.

3. Only when he screamed, did we realize that he was injured.

4. Only under special circumstances, will approval be granted.