仙人掌生活在生态环境恶劣地区，它的叶特化为刺，绿色的茎膨大呈掌状、棒状，能进行光合作用。这些特点适应什么样的生存条件[]A．缺乏空气B．缺乏阳光C．缺乏水分D．缺乏营养-七年级生物

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• — Whose guitar is this? — It ______ Alice. She plays the guitar. [ ]A. might be B. must be C. can be
• — Need I have a drive license to drive a car? — Yes, you_____or you might be caught and fined by the
• —Need I go there with you? — Yes, you _____. [ ]A. need B. mayC. must D. can -九年级英语
• — Mum, Must I do my homework first today?— No, you _____. You _____ watch TV or play with your frien
• Someone is knocking at the door. It my mother. It's time for her to be back. [ ]A. can be B. ma
• — Don't forget to go to see Mum on her birthday.— No, I ______. [ ]A. don't B. can't
• — Shall I tell John about it? — If I were you, I _____. He is a dishonest man. [ ]A. will B. won
• —How nice the building is! What is it used for? —It as a hotel. But I'm not sure. [ ]A. must be
• — Where is Tom? — He hasn't come to school today. I think he ______ be ill. [ ]A. has to B. sho
• — Look! The people are fighting over there. Let's go to stop them. — Can't you see? Many p
• —What ______ we do if we had a million dollars?— That's only a dream. [ ]A．must B．would C．will
• Youjump onto a bus while it is moving. It's too dangerous.[ ]A. may not B. mustn't C. may
• If anyone wants to say something in class, you ______ put up your hands first. [ ]A. mustB. mayC. sh
• You are too busy, so you keep any pets. [ ]A. ought toB. ought not toC. could D. should -八年级英语
• Don't go hiking alone here. You _____ get lost. [ ]A. can B. must C. may D. should-九年级英语
• — ______ I visit Lucy on Sunday, Mum? — Yes, you______. [ ]A. Must; can B. May; may C. Need; need D
• —Look! The man standing there is Mr Green.— It ______ be Mr Green. He has gone to England. [ ]A．can&
• Look out! The knife is very sharp. You _____ cut your finger. [ ]A. must B. need C. should D. may -八
• You _______ worry about him. He will get well soon. [ ]A. needn't B. can't C. mustn't
• 请据图回答下列问题：（1）对吸入气体有过滤，湿润和温暖作用的结构是图一中的[______]______．（2）图二中的b代表的物质是______，血液从毛细血管[4]______端流到[5]_____
• —Tom, where is your father? — I'm not sure. He ______ in his office. [ ]A. is B. may be C. mayb
• — Listen! There is a strange noise over there. — There _____ some dangerous animals. Let's run
• Though it's cloudy now, it ______ get sunny later.[ ]A. can B. mayC. mustD. need -九年级英语
• 句型转换。1. May I smoke here? (否定回答)No, . 2. Look! There is some milk in the glass. (改为否定句)Look! There m
• 如图是人体呼吸系统结构图（1）在横线上填出各部位名称．1．______2．______3．______4．______5．______（2）人体的呼吸系统由______和______两部分构成，其中能
• The book be Lucy's because her name is on the cover. [ ]A. must B. can C. need D. does -九年级英语
• — Can you go swimming with us this afternoon?— Sorry, I can't. I ______ take care of my little
• —Must I go and repair our TV set this afternoon?—No, you _______. I've repaired it.[ ]A. mustn&
• 呼吸系统由呼吸道和______组成，后者是呼吸系统的主要器官，它是______的场所，呼吸道的作用是将吸入的空气变得______、______、______，减少对器官的刺激．-七年级生物
• — Daddy, I can see only a few stars in the sky. — Oh, my son. Many of stars ____ because they are to
• — It's the classroom! So you ______ know smoking is not allowed here.— Oh, sorry. [ ]A. need B.
• — Must I take my umbrella?— No, you ______. It's not going to rain. [ ]A. mustn't B. needn
• 呼吸系统的起始器官是（）A．鼻B．咽C．口腔D．喉-生物
• — May I have a look? — Sorry, _______. [ ]A. please B.you may C. you may not D. you mustn't -八年
• 人体的呼吸系统是由呼吸道和和肺组成，其中鼻、咽、______、气管、______组成呼吸道，是气体进出______的通道．-七年级生物
• 血液经过肺循环后，其变化是（）A．由动脉血变成静脉血B．由含养料变成含废物C．由静脉血变成动脉血D．由含废物变成含养料-九年级生物
• 人体的呼吸系统是由______和______构成的．其中，气体交换的主要场所是：______，能对空气进行处理的是______．-七年级生物
• If I went to the moon, I ______ bring something unusual back to the earth. [ ]A. can B. will C. woul
• He has bought a new car. It _______ be very expensive. [ ]A. can B. can't C. must D. mustn'
• You_______ to the meeting this afternoon if you have something important to do. [ ]A. needn't t
• —_______ you pass me a pen? I'd like to write down the phone number.—Sure. Here it is. [ ]A. Ca
• 连线题：骨骼神经系统肺运动系统心脏呼吸系统大脑循环．-生物
• The news be true. I know everything about it. [ ]A. can'tB. mustn'tC. needn't D. may
• 呼吸系统由______和______组成．其中呼吸道由______（使空气温暖、______，是气体进出肺的通道）；气体交换的场所，是呼吸系统中最重要的器官是______．-七年级生物
• I think students _______ to do homework with friends.[ ]A. should allowB. should be allowedC. were a
• Cars and buses _____ stop when the traffic lights turn red. [ ]A. canB. mayC. must D. need-九年级英语
• 下列不属于呼吸系统的是（）A．喉B．肺C．胃D．气管-七年级生物
• 如图为人体呼吸系统结构模式图．请回答：（1）图中气体和食物的共同通道是[______]______．（2）“痰液”形成于[______]______．（3）图中完成气体交换的中心场所是[______]
• — Hello. May I speak to Tom?— I'm sorry. You ____ the wrong number. There's no one here by
• 呼吸系统由______和______组成；其中______能使吸入的气体变得温暖、湿润、清洁．-生物