代词指代问题，求大神指点~~

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。

7.I took it for granted that they were not coming.
我想他们准是不会来的了。
8.I’ll see to it that everything is ready in time.
我负责使一切都按时准备好。