并列句中,如果句型相同,如都是主谓宾结构,后面一个句子的主语与前面句子的主语相同就可以省略主语.如果是主系表结构,后面一个句子的系动词就可以省略. 比如: He likes dancing.He also likes singing.这两句话都是主谓宾结构,所以就可以用and 合并为一个并列句,后一句省略主语he.即:He likes dancing and singing. 又如:Tom's hat is blue.Lily's hat is red.这两句是主系表结构.主语不同,但系动词相同都是is.那么就可以合为:Tom's hat is blue,and Lily's red.为了简洁.