14 Have to与must的用法-【暑假预习】2023新七年级英语核心知识点与常见题型通关讲解练（牛津译林版）

14 Have to与must的用法 第一部分 语法知识梳理 have to 表示不得不，说明客观条件只能如此；有时态形式的变化；否定式don’t have to意为＂不必＂(= needn’t) My brother was very ill, so I had to call the doctor in the midnight. 我弟弟病得厉害，我只得半夜里把医生请来。 I haven’t got any money with me, so I’ll have to borrow some from my friend. 我身上没带钱，只好向朋友借点了。 must 表示必须，一定要，指说话人的主观语气 You must obey the school rules. 你必须遵守校规。 mustn’t表示禁止，意为＂千万不要，禁止＂，是说话人强有力的劝告 You mustn’t play with the knife or you may hurt yourself. 你禁止玩刀否则你可能会伤到自己。 表示推测时，用于肯定句，意为＂想必，一定＂，否定句中用can’t/couldn’t来代替 This must be your room. 这一定是你的房间。 He must be eighty now. 他现在想必有八十岁了。 【知识拓展】 1. must的一般疑问句，肯定回答为Yes, ...must.；否定回答为No, ...needn’t./No, ...don’t have to. —Must I clean the classroom now? 我必须现在打扫教室吗？ —Yes, you must. 是的，你必须。/No, you don’t have to. /No, you needn’t. 不，你不必。 2. must和have to的区别： ①用must表示＂必须＂的意思时，通常着重于说话者的主观看法，认为有必要去做某事；而have to着重于客观需要，含有＂不得不＂的意思。 We must study English hard. 我们必须努力学习英语。 You are ill today. You have to see a doctor. 你今天病了，不得不去看医生。 ②用must表示＂必须＂，只有现在时态的形式，如果要表示过去时或将来时的＂必须＂，就要用have to的相应形式。 You must drive fast to catch the time. 你必须开车开快点来赶时间。 They will have to leave tomorrow morning. 他们必须明天早晨起程。 第二部分 Have to与must的用法专项训练（含解析） 一、单项选择 1．— Dad, why should I stop ______ computer games? — For your health, my boy, I’m afraid you ______. A．to play; must B．playing; have to C．to play; can D．playing; may 2．—Doesn’t Frank like staying at home and looking after his little sister? —_______, but he ________ because both of his parents work. A．Yes; has to B．No; has to C．Yes; doesn’t have to D．No; doesn’t have to 3．—Must I finish all the homework today? —No, you ________. You can leave some for tomorrow. But you should do all your homework on your own. You ________ copy others’. A．needn’t; needn’t B．don’t have to; needn’t C．mustn’t; mustn’t D．don’t have to; mustn’t 4．His arm is all right. He___ go and see the doctor. A．has not to B．don't have to C．haven't to D．doesn't have to 5．—Mum, must I take out the rubbish now? —No, you _____. You may take a