非谓语动词的句法功能一作主语A . 不定式 To see is to believe. (强调具体行动更强调一次性)B.–ingSeeing is believing. 眼见为实 (一般行为)C. the+过去分词 表一类人The injured were sent to hospital.常用不定式的惯用句1. It is + adj. +to do sth eg: It is not safe to drink the polluted water.It is + adj.+of sb to do sth for sb to do sth