2.My mother knows Jane; they ( ) to each other at a party.

解析:(主动语态:introduce sb. to sb.)解析:被动语态部分还须特别注意动词make, hear, see等词,其后面用动词不定式作补足语时,to 应该保留。解析:Those who won＇t work should be made to work.解析:The teacher was made to give up his teaching because of poor health.(give up 放弃;health 名词;healthy 形容词;breath 名词;breathe 动词)