1、省略主语 祈使句中主语通常省略；其它省略主语多限于少数现成的说法。
(1) (I) Thank you for your help.
(2) (I) See you tomorrow.
(3) (It) Doesn’t matter.
(4) (I) Beg your pardon
2、省略主谓或主谓语的一部分
(1) (There is) No smoking .
(2) (Is there) Anything wrong ?
(3) (Will you) Have a smoke ?
(4) What/How (do you think) about a cup of tea ?
(5) Why (do you) not say hello to him ?
3、省略作宾语的不定式短语，只保留to，但如果该宾语是动词be或完成时态，则须在之后加上be或have:
(1) –Are you going there? --Yes, I’d like to (go there).
(2) He didn’t give me the chance, though he had promised to (give me the chance).
(3) –Are you an engineer? --No, but I want to be.
(4) –He hasn’t finished the task yet. --Well, he ought to have.
4、省略表语
(1) –Are you thirsty? --Yes, I am (thirsty).
 

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