题目

To tell your father the truth is necessary 转换成用it 作形式主语
还有几个：That the police keep order in an important football match is a hard job 转换成用it 作形式主语。
I think it is important to master a foreign language 转换成用it 作形式宾语
He felt that it was his duty to help the poor 转换成用it 作形式宾语
I find that it's no good trying to persuade him转换成用it作形式宾语
The football match had to be put off because of the bad weather 转换成对画线部分进行强调。because of the bad weather是画线部分

提问时间：2020-07-25

答案

it 作形式主语的句子结构是 It‘s ...for sb to do sth所以这句应该改为 It's necessary to tell your father the truth.