关于生态系统的能量流动，下列叙述中正确的是[]A．稳定的生态系统必须不断地从外界获取能量B．生态系统中的能量最终来自于太阳能C．生态系统的能量流动可以循环进行，提高能量的-八年级生物

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• The desk is not dirty. You _____clean it.[ ]A. mustn'tB. shouldn't C. needn't D. can&
• You _ be tired after playing sports for a long time without a rest.[ ]A. mustB. need C. can't-八
• You _____be tired after working for eight hours without a rest.[ ]A. canB. mayC. must D. need-八年级英语
• Schools allow students to do at least one hour's sports every day after school. [ ]A. wouldB. m
• You _____be careful next time. It is very dangerous to stay alone in the forest.[ ]A. mustB. canC. w
• —Can I go to the park, Mum?—Certainly. But you ______ be back by six o'clock. [ ]A. can B. may
• We ________fight against pollution.[ ]A. may B. shouldC.mustn't D. needn't-八年级英语
• 在生态系统的能量流动中，能量形式的转变顺序是[]A．光能→化学能→热能B．热能→光能→化学能C．化学能→光能→热能D．光能→热能→化学能-八年级生物
• — Have you heard that some bad thing would happen in 2012?— Don't worry! The news_____ be true.
• With the help of the new technology, you_____ e-mail your friends by mobile phone.[ ]A. canB. mustC.
• —I borrow your MP3? —Sure. Here you are! [ ]A. MayB. ShouldC. MustD. Would-八年级英语
• You look too tired. Yourest andwork too much.[ ]A. should; shouldB. shouldn't; shouldn'tC.
• You go and ask Meimei. Sheknow the answer.[ ]A. must, may B. must, stayC. need, can D. can, may-七年级英
• —Whoseisthepencilbox?—It__________beTom's.Lookathisnameonthecover![ ]A.canB.mayC.mustD.need -九年
• —Could you go to the beach with us this weekend?—I'm sorry I can't. I ______ study for the
• It’s too dark.I ________ go home.[ ]A. canB. have toC. needD. may -七年级英语
• Where is Jack ?Sorry, I don’t know. Go and ask his brother.He _____ know.[ ]A. can B. mayC. mustD. n
• 生态系统中，能量沿着食物链传递、逐级递减。[]-八年级生物
• —_______you speak French?—No, I can’t.[ ]A. Can B. MustC. May D. Should-七年级英语
• —Where is my English book?—__________ it's in your bag or it __________ in your desk.A. Maybe;
• —May I take the magazine out of the reading room? —No, you can't. You_____ read it here. It
• My sister is ill, and shestay in bed for several days.[ ]A. need B. mustC. has to D. has to be-八年级英语
• -Can he play the guitar?-_____, and he can play it well.[ ]A. Yes, he can.B. No, he can't.C. Ye
• —I have a fever.—You _____ drink lots of water.[ ]A. are B. should C. don't D. shouldn't-八
• Dan_______come to the ceremony tomorrow. I'm not very sure.[ ]A. mayB. mustC. should D. need-九年
• —Can I park my car here?—Sorry ! Youdo it. No parking is allowed here.[ ]A. may not B. don'tC.
• I wish I _____ be a doctor.[ ]A. canB. willC. amD. could-九年级英语
• You_______ buy the TV guide for next week. I have already bought a copy. [ ]A. mustn'tB. needn&
• 改写同义，每空一词。1. How is the weather?____ ____ the weather ____?2. What can I do for you?____I____ you?3.
• 以下是我国生态农业的例子。资料一：广东利用赤眼蜂防治稻纵卷叶螟，取得了良好的效果。在华北地区利用杉毛虫、显眼蜂防治玉米螟，可以代替农药。资料二：在我国很多农村，沼气-八年级生物
• _____ you like to ring up your father? [ ]A. WouldB. Can C. ShallD. Must-八年级英语
• You____eat____food if you want to keep slim.[ ]A. should;littleB.must: littleC. should;lessD.should:
• Lookout!Theknifeisverysharp.You________cutyourfinger.[ ]A.mustB.shouldC.mayD.need -七年级英语
• You ______________ in class.[ ]A. don'tB. can'tC. notD. no-七年级英语
• That man ______ be my English teacher. He has gone to Canada.[ ]A. needn’tB. mustn’tC. can’t-九年级英语
• —What's wrong with you? You looked tired.—Last night I _____ sleep well.[ ]A.couldn'tB.wou
• 从方框中选择适当的情态动词，并用其正确形式填空。can, must1. _____ you see those people over there?2. You _____ play fire, be
• Our manager is out. _____ I take a message? [ ]A. Can B. Should C. MustD. Do-八年级英语
• “螳螂捕蝉，黄雀在后”，形容人们做事时常常顾此失彼。我国内蒙古自治区东乌旗牧区，“草肥水美”。牧民们世代在这里居住和放牧。在1960年以前的草原上还生存有狐狸、狼、野驴等-八年级生物
• Jane _________ to carry heavy things. She is very strong.[ ]A. canB. ableC. is ableD. could-八年级英语
• Ads sometimes help people learn more about new products, but at other times ads _______tell lies. [
• —What can Tony do? —He can __ the guitar. [ ]A. is playing B. playing C. plays D. play-七年级英语
• I certainly wondered what my parents _____.[ ]A. are doingB. will do C. wouldD. have done-九年级英语
• __ I get home before 7 ?no, you needn’t.[ ]A.Must B.Should C.Can D. Will-八年级英语
• All of them thought we _________ finish so much work in one day. It was too hard for us.[ ]A. canB.
• 句型转换，每空一词。1. Hello ! I'd like to speak to John.(疑问句) Hi! ___ I__to John?2. Hi! Is Wang Hua at h
• MrsSmith________beathomenow.SheflewtoHainanthismorning.[ ]A.mustn'tB.can'tC.maynotD.needn&
• You ________ go and help him with the housework.[ ]A. don't needB. not needC. needn't toD.
• —Must I take the medicine every day?—No, you______.[ ]A. must not B. may not C. haven’t D. needn
• The front road was washed away, so we _____ get off the bus and walk over. [ ]A. must B. had toC. sh