并列结构的省略 (Omission Through Coordination)

　　1. 在并列结构中，如果后面分句中有与前面相同的部分，就常被省略，以免重复，如：
　　　　Bob has done his homework, but Tom hasn't (done his homework).
　　　　She was poor but (she was) honest.
　　　　I have to give up the job and (I have to) leave the city.

　　2. 并列句中后一分句的部分省略表示一个事后想起的意念，如：
　　　　He did it and quite successfully (did it) too at the beginning.
　　　　This happened and a good thing (happened) too for it helped us to realize our shortcomings.