省略可以分为实词的省略与虚词的省略。虚词的省略包括连接词，助词，介词以及不定式符号的省略，实词的省略包括做主语或宾语的名词与代词，不定式动词的省略。
一、虚词的省略
1、连接词的省略：
①限定性定语从句关系代词做谓语的宾语 Is there anything (that) I can do for you?
②宾语从句连接词that They know (that) the habit will kill them.
③含有虚拟语气的状语从句用倒装语序 Had we booked a table earlier, we couldn't be standing here in a queue.
2. 不定式符号的省略：
①不定式做使役动词宾语补语 We will have the students write a passage about the internet.
②不定式做表语，主语部分有实义动词do What doctors can do is save people's life.
③不定式做介词but, except，besides宾语且前面有实义动词do There was nothing to do but wait till he came back.
④在并列结构中承前省略 We are happy to learn from others and share our own experiences.
⑤情态动词后的不定式 You'd better return the book to the library on time.
3、介词的省略：Stop sb (from) doing; be busy (in) doing; have difficulty/ trouble (in) doing ; spend time (in) doing
二、实词的省略
1.名词、代词的省略:
①并列复合句主语承前省略 He is rich, but leads a modest life.
②祈使句 Tell me what you are going through in your mind.
③状语从句的主语与
主句主语是同一个人或物 When asked about the advertising campaign of the new product，the manager said it was a great success.
2、动词的省略：
省略不定式动词，只保留不定式符号
The boy wanted to ride his bicycle in the street, but his father told him not to.