“it+系动词+过去分词+that从句”造句

1.It is said that 据说（＝people say 即大家都这么说）that 后面接一个从句,that 可省略.例：
It is said （that） he is only 13 years old.据说他才13岁.
=He is said to be only 13 years old.他据说才13岁.
其它几个的用法都是一样.
2.It is thought （that）大家认为.有人认为.that后同样接一个句子.例：
It is thought （that ）he is the greatest person in the world.他被认为是世界上最伟大的人（同样请写出另两种表达）.
3.It is known that 众所周知.
4.It is reported that 据报道.有报道称.
5.It is estimated that 据估计.
6..It is believed that 据信.大家相信.