什么是省略句?

省略句用法
1.省略句是省略主语，谓语动词或从句的句子。
Thank you very much.
非常感谢。（省略主语。）
Tom goes to school, Jill to the kindergarten.
汤姆去上学，吉尔去幼儿园。（省略谓语动词goes。）
If necessary, I will go to the hospital.
如果有必要，我就去医院。（省略主语和谓语动词，原句是If it is necessary， I will go to the hospital。）
A:Who didn't pass the examination?
B:I don't know.
A：谁没有通过考试？
B：我不知道。（省略从句，原句是I don't know who didn't pass the examination。）
2.DO可以用来代替一般动词或一般动词和它后面的宾语。
He got up early, and I did, too.
他早起，我也早起。（did代替got up early。）
I bought a book, and he did, too.
我买了一本书，他也买了一本。（did代替bought a book。）