1.如果并列句的左右两个分句主语虽然不同，但是两个分句有相同的be动词，那么可以省略连词和后一个分句的be动词。

例句：

Its scientists were the world’s best , its workers the most skilled.

→Its scientists were the world’s best , (省略and)its workers (省略were) the most skilled.

它的科学家是世界上最好的，他的工人是世界上最熟练的。

It is said that in England death is pressing , in Canada inevitable and in California optional .

→It is said that in England death is pressing ,(省略and) in Canada (省略death is )inevitable and in California (省略death is )optional .

据说，在英国死亡时迫在眉睫的，在加拿大死亡时不可避免的，而在加利福尼亚死亡则是可以选择的。

2.如果并列句中左右两个分句出现重复的部分，那么后一个分句可以省略重复的部分，但是没重复的部分要保留。

例句

Do you remember all those years when scientists argued that smoking would kill us but the doubters insisted that we did not know for sure?

→Do you remember all those years when scientists argued that smoking would kill us but the doubters insisted that we did not know(省略that smoking would kill us ) for sure?

你还记得那些年科学家说吸烟会致命，但怀疑者坚持说我们并不确定吸烟是否真的会致命吗?

3.在并列句中后边的分句可以省略与前边分句中相同的成分

Tom picked up a coin in the road and handed it to a policeman.

→Tom picked up a coin in the road and (省略Tom )handed it to a policeman.

汤姆在马路上拾起一枚硬币并把它交给了警察。

Tom must have been playing Dota and Mary cooking the dinner .

→Tom must have been playing Dota and Mary(省略must have been) cooking the dinner .

汤姆肯定在打魔兽，玛丽一直在做晚饭。