文档介绍：world world today yesterday … tomorrow Tomorrow ’ s world Unit3 The man _________(call) “ Good husband ”. is called The pet dog ________________(treat) by veterinary. is being treated A frog __________ ( catch) by a big bird just now. was caught An argument _____ already __________ __________ (put forward) has been put forward When do we use the passive voice ? Many houses will be built here. 1. 不知道或没必要指出动作的执行者。 The song “ The East is Red ” was written by a poor peasant. 2. 强调动作的承受者。 The plan was supported by those who wished to have more chances to speak English. 3. 动作的执行者有较长的修饰语。 You are requested to attend the meeting. 4. 出于礼貌,不愿意说出动作的执行者。