Unit 10 You're supposed to shake hands 单元语法清-【四清导航•辽宁专版】2022-2023学年九年级英语下册作业课件(人教版)

单元语法清 英语 九年级下册 人教版 四清导航 语法精讲 一、be supposed to do sth.的用法 be supposed to do sth.中的to是动词不定式符号，其后要跟动词原形；be动词随主语的人称、数和时态的变化而变化。 1．be supposed to do sth.意为“应该做某事”，它可以表示劝告、建议、义务、责任等，相当于情态动词should。如： Everyone is supposed to wear a seat belt in a car.每个人在坐车时都应该系安全带。 2．其否定形式为：be not supposed to do sth.，常用于口语中，意为“不被许可/不应该做某事”。如： You are not supposed to smoke on the bus.你不应该在公交车上抽烟。 2 3．其一般疑问句形式为：Be＋主语＋supposed to do＋其他？如： Was Lucy supposed to lock the door when she left the classroom? 当露西离开教室时，她应该锁门吗？ 4．其特殊疑问句形式为：特殊疑问词＋be＋主语＋supposed to do＋其他？如： What are we supposed to do to save water in our daily life? 在日常生活中，我们应该做什么来节约用水？ 5．was/were supposed to do sth.相当于should have done sth.表示过去本应该做某事而并没有做。如： The train was supposed to arrive half an hour ago.火车本该在半小时之前到达。 3 二、be expected to的用法 be expected to意为“被期望……”，表示一种可能性。其中to是动词不定式符号，其后要接动词原形。be动词有人称和时态的变化，其否定形式要在be动词后加not。如： She is expected to be a good doctor.她有望成为一名好医生。 三、“It is＋adj.＋to do sth.”句式的用法 “It is＋adj.＋to do sth.”为固定句型，其中it是形式主语，真正的主语是动词不定式(短语)。因为动词不定式(短语)作主语相对较长，为了避免头重脚轻，所以用it作形式主语。 【拓展】(1)“It is＋adj.＋for sb. to do sth.”意为“对某人来说做某事是……的”。此句型中的形容词常用于表示事物的特征、特点，如easy，impossible，difficult，interesting，important，hard等，用来说明后面的动词不定式(短语)。如： It's hard for me to answer your question.我很难回答你的问题。 5 (2)“It is＋adj.＋of sb. to do sth.”意为“做某事某人是……的”。此句型中的形容词常用于表示人物的性格、品德，如good，kind，nice，clever，polite等，用来说明of后的sb.。如： It's very kind of you to help me with my English.你帮助我学习英语真是太好了 6 语法精练 一、单项选择。 ( )1.Parents are ________ to teach their children how to develop a good habit. A．taught B．allowed C．supported D．supposed ( )2.Students are not supposed ________ loudly in the reading room. A．speak B．speaking C．to speak D．spoke ( )3.She ________ to clean the tables after dinner，but she forgot it. A．is supposing B．is supposed C．was supposing D．was supposed D C D ( )4.We are supposed ________ with some housework at home when we have free time. A．to help B．helping C．helped