原七年級(jí)英語下冊 Unit 4 Don't eat in class（第3課時(shí)）(Grammar Focus3c)同步語法精講精練課件 （新版）人教新目標(biāo)版

Unit 4Dont eat in class.第三課時(shí)(Grammar Focus3c)單元同步語法精講精練 含義：含義：祈使句是用來表示請求、命令或建議等的一種句型。其主語一般祈使句是用來表示請求、命令或建議等的一種句型。其主語一般為第二人稱為第二人稱you，但通常省略。祈使句的句末一般用句號(hào)但通常省略。祈使句的句末一般用句號(hào)，表示較強(qiáng)語氣時(shí)表示較強(qiáng)語氣時(shí)用感嘆號(hào)。為了使祈使句顯得更委婉、有禮貌用感嘆號(hào)。為了使祈使句顯得更委婉、有禮貌，可在開頭或結(jié)尾加上可在開頭或結(jié)尾加上please。 祈使句的四種類型祈使句的四種類型Do型祈使句：實(shí)義動(dòng)詞原形其他型祈使句：實(shí)義動(dòng)詞原形其他eg：Listen to me，please.請聽我說。請聽我說。Be型祈使句：型祈使句：be動(dòng)詞其他動(dòng)詞其他eg：Be quiet，please.請安靜。請安靜。Let型祈使句：型祈使句：Letsb.動(dòng)詞原形其他動(dòng)詞原形其他eg：Lets play football.讓我們踢足球吧。讓我們踢足球吧。eg：No smoking！禁止吸煙！No photos！禁止拍照！ 祈使句的否定形式通常是在謂語動(dòng)詞前加dont。但要注意以let開頭的祈使句，其否定形式是：“Dontlet賓語動(dòng)詞原形其他”或“Let賓語not動(dòng)詞原形其他”。eg：Dont let him go swimming.Let him not go swimming.不要讓他去游泳。情態(tài)動(dòng)詞can與have to情態(tài)動(dòng)詞can的用法can意為“能；會(huì)”，表示做某事的能力，其否定形式為cant。eg：Can you speak English？你會(huì)講英語嗎？can還可表示“允許；許可”。eg：You cant eat in class.你不能在課堂上吃東西。情態(tài)動(dòng)詞have to的用法have to意為“必須；不得不”，其后接動(dòng)詞原形。have to有第三人稱單數(shù)形式，即has to，變疑問句和否定句要借助助動(dòng)詞do/does。eg：We have to go home after school.我們放學(xué)后必須回家。 一、用所給單詞的適當(dāng)形式填空。一、用所給單詞的適當(dāng)形式填空。1 (not play) with fire (火火)2Dont (run) in the classroom.3Let him (not play) the computer games.4Can we (eat) here?5Do you have to (go) to bed before ten at night?Dont playrunnot playeatgo二、單項(xiàng)選擇。6_ listen to music in the classroom.ANotBNoCDontDBe not7Tom，please _ the classroom now.Aclean Bto clean Ccleans Dcleaning8Lets _ on time for classes.Abe Bbe not Care DisCAA9She has to _ her homework every night.Adoes Bdo Cdoing Dis doing10Sorry，you _ play basketball in the classroom.Acant BdontCdont have to DarentBA三、按要求完成下列句子。三、按要求完成下列句子。11Lily can play the guitar.(改為一般疑問句并作否定回答改為一般疑問句并作否定回答) Lily the guitar? ，she 12Jack has to play the piano every weekend.(改為一般疑問句改為一般疑問句) Jack play the piano every weekend?13Be quick.(改為否定句改為否定句)Dont be quick.Can playNocantDoeshave to14You cant eat food in class.(改為祈使句改為祈使句)Dont eat food in class.15You must walk to school today.(改為祈使句改為祈使句)Walk to school today.16You cant be late for class next time.(改為祈使句改為祈使句)Dont be late for class next time.