从句的种类及使用方法
从句的种类及使用方法如下：
1.主语从句
1）主语从句可直接位于主语的位置，如果从句较长，谓语又较短，可用it作形式主语，而将从句放在句末。常见的句型有：
*It is a fact\a pity\a question\good news that...
*It seems\appears\happened\has turned out that...
*It is clear\important\likely\possible that...
*It is said\reported\estimated\has been proved that...
It is said that comic books create a connection between people of the same generation.
It seems that the performance is very useful.
2)what引导的主语从句表示“...的东西时”，一般不用it作形式主语。
What we lack is experience.
3)what,who,when,why,whether等词含有各自的疑问意义，但它们引导的主语从句，都用陈述语序。
How the plan is to be carried out should be discussed again.
I did know why I felt like crying.
2.宾语从句
1）宾语从句可位于及物动词、介词和某些形容词后。连词that常可省略。介词后一般接疑问词引导的宾语从句。in that(因为),except that(除了),but that(只是）已构成固定搭配，其他介词后一般不接that引导的宾语从句。
*I promised that I would change the situation.
*All this is different from what American young people would say about friendship.
*He is certain that watching so much television is not good for children.
*This article is well-written except that it is a bit too long.
2)宾语从句后如有宾补，要用形式宾语it来代替，而把宾语从句移至宾补之后。
