It,that与this的区别如下面这句话Some people have won two prizes , but this is rare.类似这种句子,我不太明白什么时候用this , it , that ,请各位指点一下.

问题描述:

It,that与this的区别
如下面这句话
Some people have won two prizes , but this is rare.
类似这种句子,我不太明白什么时候用this , it , that ,请各位指点一下.