句型转换。
1．They all knew that William had broken his promise.（用it作形式主语）
_______________ all that William had broken his promise.
2．I don’t think it is possible to master a foreign language without much memory work.（用it作形式宾语）
I don’t think _______________ to master a foreign language without much memory work.
3．He felt it was his duty to work human rights and progress.（用it作形式宾语）
He felt _______________ to work for human rights and progress.
4．He found it was difficult to find a job nowadays.（用it作形式宾语）
He found _______________ to find a job nowadays.
5．He let his friends know that he didn’t want to enter politics. （用it作形式宾语）
He made _______________ that he didn’t want to enter politics.
6．The newspaper says that the bridge is of poor quality. （用it作形式主语）
_______________ that the bridge is of poor quality.
7．In the west, people send Christmas presents to their relatives and friends, making it a rule. （用it作形式宾语）
I the west, people _______________ to send Christmas presents to their relatives and friends.
8．We thought it was strange that Mr. Smith did not come last night. （用it作形式宾语）
We _______________ Mr. Smith did not come last night.
