下列关于生态系统中能最流动的叙述，正确的是（）A．可循环的，逐级递减B．可循环的，逐级递增C．单方向的，逐级递增D．单方向的，逐级递减-八年级生物

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• “螳螂捕蝉，黄雀在后”中的三种动物属于生态系统中的（）A．生产者B．消费者C．分解者D．非生物部分-七年级生物
• —Whose purple coat is this?—It ____ be Lily’s. Hers is red. It _____ be Lucy’s. She likes purple.A．m
• 用be动词的适当形式填空。1. My name _____ Jack. 2. She _____Julia Roberts. 3. I _____a girl. 4. Tom and Mark ___
• —___________ he have to wear his school uniform every day?—No, he ______________.A．Must; mustn'
• ——Can I walk across the road now, mum?——No, you_______. You have to wait until the light turns green
• The food in the restaurant _____ delicious and the music sounds _____.[ ]A. look, beautifully B. sme
• —Is the boy by the window your brother?—It ______ him. [ ]A. maybe B. may beC. would beD. need be-八年
• ---Is that Lucy’s sister, Lily?---No, it _______ be her. She has gone to English.A．couldB．canC．can’t
• I have no money on me. I ______ go to the bank and get some money. [ ]A. shouldn't B. must C. h
• 如图为一个草原生态系统的一角：蝴蝶在花草间飞舞，蜜蜂在采食花粉和花蜜，蝗虫和蝴蝶的幼虫在啃食草叶，蚂蚁在忙碌地往洞穴中搬运草籽，而蜘蛛却张开了大网，等待那些没有意-七年级生物
• — What did the head teacher say at the meeting? — He said, "We _____be proud of working hard. W
• 用be的正确形式填空。1. I ______ Daming. 2. How ______ you, Lingling? 3. This girl ______ my friend. -七年级英语
• -- Could I invite my friends to my birthday party? -- Sorry, you _________.A．canB．can’tC．couldD．coul
• These shoes aren’t comfortable. You __________ wear them.A．shouldB．couldC．shouldn’tD．can-八年级英语
• There is going to _____ a parents' meeting this evening. My father will take part in it.[ ]A. h
• Mr. Black used to_____ a teacher. But now he is a writer.[ ]A. /B. beC. isD. being-八年级英语
• 用所给单词的适当形式填空。1. There _____(be) one desk and two chairs in the classroom. 2. There _____(be) three c
• 下列生物属于分解者的是（）A．水藻B．真菌C．大豆D．鱼-七年级生物
• The magazinebe Lily's. Look, her name is on its cover.[ ]A. mayB. might C. couldD. must-九年级英语
• There is going to_____ a class meeting tomorrow.[ ]A. to beB. beC. haveD. has-七年级英语
• —Could you come to my birthday party?—Sorry, I ________.A. couldn’t B. can’t C. can-八年级英语
• --______ you leave now?---Yes, because I’m meeting my aunt at 7:00 this evening.A．CanB．MayC．NeedD．Mu
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• —Whatthe weathertoday? —It's cold.[ ]A. it;/B. is; likeC. does; likeD. can; be-七年级英语
• “I hope you _______ come and see me soon” said Grandma Li to her son.A．toB．canC．will beD．are going t
• —_______ youswim?—Yes,butI'mnotagoodswimmer.[ ]A.CanB.MayC.NeedD.Must-九年级英语
• —Mary,____you speak Chinese?—Yes, only a little. [ ]A. must B. need C. may D. can -八年级英语
• 有所给词的适当形式填空。1. Could you please _____ (sweep) the floor? 2. They have to _____ (get) home to do thei
• You ___________ finish the report today. Any time before this weekend is OK.A．mustn’tB．needn’tC．must
• 看图完成下列问题：在一片草原的生态系统中，昆虫以草为食，青蛙以昆虫为食．三者的相互关系用右图表示，图中各长方形的面积分别表示上述三种生物的数量，长方形越长表示该生物-七年级生物
• 在生态系统中______是生产者，能通过光合作用制造有机物；绝大多数______作为消费者，他们直接或者间接地以植物为食，营腐生生活的细菌、真菌是分解者．-七年级生物
• —Must I go there right now, mum?—No, you ____. You can go there tomorrow.A．shouldn’tB．can’tC．mustn’t
• 改错。1.The jeansmade of cotton. AB C2.May I use your notebook? Yes.I may.A BC3.Millie isdressing up a
• I ______ Lucy King. ______ you Li Lei? [ ]A. am; Am B. am; Is C . am; Are-七年级英语
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• The number of the students in that school ________ three thousand.[ ]A. areB. is C. have D. has-八年级英
• – May I take the magazine out of the reading room?-- No, you can’t. You read it here. It’s the rule.
• -There is someone knocking at the door.- It ______ be Jimmy, he has gone to ShangHai .A．needn’tB．mus
• The light is still _________. Mr. Green _________ at home now. [ ]A. on, can be B. down, may be C. o
• 下列生物中属于消费者的是（）A．草B．食虫鸟C．细菌D．蘑菇-七年级生物
• 消费者指（）A．能自己制造有机物的生物B．不能自己制造有机物的生物C．能分解有机物的生物D．以上都不对-七年级生物
• —Hurry up, Mum. The lights are turned on. Dad has been back.—It _________ be him. He has gone to Sha
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• Simon's shoes _____white. So this pair of shoes _______ his. [ ]A. is; is B. are; areC. is; are
• I want to _____ a doctor when I grow up. [ ]A. beB. doC. am D. is-七年级英语
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