/ 让学习更有效 新课备课备考 | 英语学科 / 让学习更有效 新课备课备考 | 英语学科 2025年鲁教版（五四学制）九年级全册英语精讲精练 Unit 2 Teenagers should be allowed to choose their own clothes 核心语法：被动语态中的情态动词 一、核心概念 情态动词被动语态用于表达"某事应该/可能/必须被做"的含义，其结构为： 情态动词 + be + 及物动词的过去分词（V-ed） 二、基本结构 情态动词 主动语态 被动语态 例句（被动） can can do can be done The rules can be changed. may may do may be done The project may be delayed. must must do must be done The work must be finished. should should do should be done The room should be cleaned. need need to do need to be done The car needs to be repaired. have to have to do have to be done The form has to be submitted. 三、使用场景 规则与义务 These documents must be signed before Friday.（文件必须在周五前签署） 建议与劝告 The problem should be discussed at the meeting.（问题应在会议上讨论） 可能性 The package might be delivered today.（包裹可能今天送达） 必要性 The plants need to be watered daily.（植物需要每天浇水） 四、句式转换三步法 找宾语变主语 You must complete the form. → The form must be completed. 情态动词后加be should complete → should be completed 动词变过去分词 complete → completed 注意：by+执行者通常省略，除非需要强调。 五、特殊形式 情态动词 + have been done（表示对过去的推测） The letter may have been lost in the mail.（信件可能在邮寄过程中丢失了） 否定形式 The door can't be opened without a key.（没有钥匙门无法打开） 疑问形式 Should the report be rewritten （报告需要重写吗？） 六、易错点提醒 漏掉be动词 The task must completed. → The task must be completed. 误用动词原形 The window should close. → The window should be closed. need的两种被动形式 The floor needs mopping.（主动形式表被动） The floor needs to be mopped.（被动语态） 七、记忆口诀 "情态被动很简单，情动加be加过分； must/should/can/may，后接be done记心间； 否定not加情动后，疑问情动提句前！" 1．—How often do I need to feed the dog —It _____ food every day, or it will be hungry. A．must give B．must be give C．must gave D．must be given 2．My mother told me that my homework must _____ on time. A．finish B．be finish C．be finished D．finished 3．—It's difficult to get to the other side of the river. —I think a bridge _____ over the river. A．should be built B．should build C．will build D．has built 4．—The horse-face skirt is popular. It puts together modernity and tradition naturally. —Yeah! It shows that traditional beauty should _____ by Chinese people today. A．value B．be valued C．valued 5．The lights must _____ before you leave the classroom. A．turn on B．turn off C．be turned on D．be turned off 6．Some of the stars _____ because they are too far away. A．can’t see B．can’t be seen C．mustn’t see D．mustn’t be seen 7．Something must _____ to protect the sharks because many of them are endangered now. A．do B．done C．be done 8．No matter how many difficulties we have, I believe all the problems can _____ in the end. A．solve B．be solved C．be solv ... ...
