that名詞性從句
1.引導賓語從句。及物動詞后的引導詞that可省略。
I didn't expect (that) he could win the championship.
The teacher pointed out that Tom was not working hard enough.
2.引導主語從句。通常采用it作形式主語的句型。
That the earth goes around the sun is known to everyone.
�。↖t is known to everyone that the earth goes around the sun.）
3.引導表語從句。
The trouble is that we are short of money.
4.引導同位語從句。
引導同位語從句的that和引導定語從句的that是不同的。前者只起語法作用，在從句中不作任何成分；而后者在定語從句中作主語、賓語或表語。舉例說明：
The news that he resigned from office surprised us.
The idea that he holds is very common nowadays on campus.