Module 4 Unit 3 Tomorrows world.ppt

即学即用 I think it’s high time that we ________ effective measures to prevent the accidents. A．took B．be taken C．have taken D．are taking 答案：A 完成句子 早就该是你努力学习的时候了。 It is ________ time that you ________ hard. 答案：high；studied 33 34 语法精讲 被动语态 一、被动语态 英语动词有主动语态 Active Voice 和被动语态 Passive Voice 之分。如果主语是动作或状态的[发出者]，动词就用主动语态；如果主语是动作或状态的[承受者]，动词就用被动语态。 John encouraged Mary.约翰鼓励玛丽。 Mary was encouraged by John.玛丽受到约翰鼓励。 第一句的动词 “encouraged” 是主动语态；第二句的动词 “was encouraged”是被动语态。 动词被动语态的基本形态是： 助动词be＋及物动词的过去分词(-ed分词) 动词的被动语态通常有六种时、体形式：即一般现在时、一般过去时、现在进行体、过去进行体、现在完成体和过去完成体。 1．Simple Present Tense 主动语态： I teach him. 被动语态： He is taught by me. 2．Simple Past Tense 主动语态： I taught him yesterday. 被动语态： He was taught by me yesterday. 3．Present Continuous Tense 主动语态： I am teaching him. 被动语态： He is being taught by me. 4．Past Continuous Tense 主动语态： I was teaching him when you came. 被动语态： He was being taught by me when you came. 5．Present Perfect Tense 主动语态： I have taught him. 被动语态： He has been taught by me. 6．Past Perfect Tense 主动语态： I had taught him before you came. 被动语态： He had been taught by me before you came. 7．一般将来时 Simple Future Tense 也常常有这种被动语 态形式 主动语态： I shall teach him tomorrow. 被动语态： He will be taught by me tomorrow. 二、动词由主动语态变为被动语态的步骤 1．先找出谓语动词； 2．再找出谓语动词后的宾语； 3．把宾语用作被动语态中的主语； 4．注意人称、时态和数的变化。 (1)Bruce writes a letter every week. →A letter is written by Bruce every week. (2)Li Lei mended the broken bike this morning. →The broken bike was mended by Li Lei this morning. (3)He has written two novels so far. →Two novels have been written by him so far. (4)They will plant ten trees tomorrow. →Ten trees will be planted by them tomorrow. (5)Lucy is writing a letter now. →A letter is being written by Lucy now. (6)You must lock the door when you leave. →The door must be locked when you leave. 三、主动形式表示被动意义 1．连系动词(如look，sound，smell，f