Ithinkitbadmannerstosmokeinareadingroom.为什么不用it's,是不是老师说错了?相同的Ithinkitimpolitetosmokeinareadingroom,这是什么语法?

Question

I think it bad manners to smoke in a reading room.为什么不用it's,是不是老师说错了? 相同的I think it impolite to smoke in a reading room,这是什么语法?

Answer 1

这里it作形宾
think/ find/ feel/ consider/ make/ regard/take it for granted /see to
1.I find it pleasant to work with him.
(it 作形式宾语,代替不定式短语to work with him)
我觉得和他一起工作很愉快.
2.They felt it difficult to finish the work in such a short time.
（ it 作形式宾语,代替不定式短语to finish the work in such a short time）
他们认为在这么短的时间内完成这项工作是困难的.
3.She thinks it her duty to help us.
（ it 作形式宾语,代替不定式短语to help us）
她觉得帮助我们是她的责任.
4.I think it my honor to be invited to speak here.
（ it 作形式宾语,代替不定式短语to be invited to speak here）
我觉得应邀在这儿演讲是我的荣耀.
5.Tom didn’t find it difficult to write letters in Chinese.
（ it 作形式宾语,代替不定式短语to write letters in Chinese）
汤姆发现用汉语写信不难.
6.All these noises made it impossible for me to go on with the work.
（ it 作形式宾语,代替不定式短语to go on with the work）
这些噪音使我无法继续工作.