2.一般过去时的被动语态
2.1 构成:主语(动作承受者)+ be 动词的过去式(was/were) + 过去分词( by + 施动者)
(1) She was seen first by the local doctors. 最初是当地医生给她看的病。
(2) The thief was caught by the police. 贼被警察抓获。
2.2 在不必强调或不知道施动者,或施动者不言而喻的情况下,被动语态的句子不需加 by + 施动者。
(1) She was sent to a specialist in Cardiff. 她被送到加的夫的一位专家那里。
(2) She was diagnosed as diabetic. 她被诊断患有糖尿病。