下列叙述正确的是（）A．在一个生态系统中，生产者、消费者、分解者是紧密联系、缺一不可B．维持生态平衡，就是维持生态系统内部各种生物的数量稳定不变C．人类所需的资源中，土地-生物

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• 若人吃的牛肉来自以玉米为饲料的牛，人和牛分别扮演的角色是（）A．生产者消费者B．消费者生产者C．消费者分解者D．消费者消费者-生物
• —Bill, is the pink umbrella Anna’s?—No, itbe hers. Hers is purple. [ ]A. canB. may not C. wouldD. ca
• 如图示草原生态系统，请分析回答：（1）此生态系统中的生产者是______，分解者是______、______．（2）生产者与消费者之间的关系主要是______的关系它们之间相互交叉形成了______，
• 从“狼吃羊，羊吃草”可以看出，狼体内的有机物最终来源于（）A．草B．水C．羊D．阳光-生物
• You_____ be so hurry as the time is not so late.[ ]A. mustn’t B. mustC. can notD. will not-八年级英语
• 根据句意，从方框内选择合适的情态动词完成句子。must, may, can, could, might, can’t1. The brown wallet_____be Tom’s or Bill’s
• — This capTina's. I know she has a red cap. — No, it be Tina's. I am wearing her cap now.
• —How about singing songs with me?—I’m sorry I can’t. Ihelp my father with his work. [ ]A. have toB.
• 把下列生物与它在生态系统中所占的位置用线连接-生物
• - your brother play basketball, John? -No, he .[ ]A. Is; isn'tB. Can; canC. Can; can'tD. A
• "Must I come here before eight o'clock?" "No, you ______." [ ]A. can'
• 请按各小题的要求转换句型，保持句子原意，每个空格只准填一个单词。 1．We don't usually have to get there too early. (改为同义的) We get
• 生态系统都是由生物部分和非生物部分组成，消费者是指（）A．人类B．所有动物C．细菌、真菌D．所有动物和细菌、真菌-生物
• 要使某一生态系统长期存在，除了非生物部分外，必须具有（）A．消费者和生产者B．生产者和消费者C．生产者和分解者D．生产者和人-生物
• Jack _______ swim when he was five years old. [ ]A. canB. could C. may D. must-八年级英语
• 下列说法错误的是（）A．我们饮用牛奶所获得的能量最终来自于太阳B．如果在人的皮肤表皮细胞内成功植入叶绿体，则我们人也能向植物一样进行光合作用C．植物的蒸腾作用会受到各种物-生物
• 下列各项生物中，属于生产者的是（）A．水草和小麦B．鱼虾和海带C．蘑菇和青菜D．食草鱼类和玉米-生物
• —Must I finish the job this afternoon?—Yes, you _____, but you ______ finish it now.[ ]A. must; must
• The bike _____ be Adam's. Look! His bag is on it.[ ]A. canB. mustC. can'tD. mightn't-
• —Where is Jack, please? —He_____ be in the reading room. [ ]A. need B. shall C. must D. would -九年级英语
• Maybe he can _____ in our club.[ ]A. beB. isC. /-七年级英语
• You ______ go and ask Meimai.She _____ know the answer. [ ]A. must, canB. must, mayC. need, mayD. ca
• 生态系统的组成成分有（）A．生产者、分解者和非生物成分B．生产者、初级消费者、高级消费者、分解者C．消费者、分解者、病毒、非生物成分D．生产者、消费者、分解者、非生物成分-生物
• 生态系统的结构越复杂，能量流动和物质循环的途径就越______，其抵抗外力影响的能力就越______．-生物
• Where are my keys? I _____ find them. [ ]A. aren't B. can't C. am not D. don't-七年级英语
• 某草原生态系统中生活着多种生物，其中有以植物各器官为食的羊、鼠和昆虫；有吃羊的狼；有吃昆虫的鸟；有以鼠为食的蛇；还有以鼠、蛇和鸟为食的鹰．根据上述信息回答下列问题-生物
• 在一个由草、兔、鼠、鹰组成的食物网中，正常情况下，数量最多的生物是（）A．草B．兔C．鼠D．鹰-生物
• —Mum, canI wear my jeans to school?—No, you _____ wear your school uniform.That's the school ru
• —_________ I borrow your pencil, please? —Sure. Here you are.[ ]A. NeedB. MustC. Can D. Have to-九年级英
• — you play the piano?—No. But I can play the guitar.[ ]A. Can B. May C. Must D. Should-九年级英语
• Everyone _____ fight against pollution.[ ]A. may B. should C. mustn't D. needn't-九年级英语
• ______ I do my homework first?No, you ______ do it after supper.[ ]A. Must, can B. Can,are C. Must,
• Look! The light in the room is still on. Mr. Liuat work.[ ]A. mustB. can't beC. must beD. have
• —Xiao Ming. _____ you recite the dialogue?—I think I can. Let me try. [ ]A. Do B. MayC. Must D. Can
• 动物在生物圈中属于（）A．自养生物、生产者B．自养生物、消费者C．异养生物、生产者D．异养生物、消费者-生物
• 下列有关某湖泊生态系统描述正确的是（）A．该生态系统中，草、鱼、微生物等是生物部分，水、阳光、土壤、二氧化碳、有毒物质，绿藻是非物部分B．该生态系统中，小草→小鱼→大鱼→-生物
• He can ______ the book to your sister.[ ]A. takes B. takeC. brings D. bring-七年级英语
• 如图为生态系统碳循环示意图，①、②、③代表的生物成分依次是（）A．生产者、消费者、分解者B．分解者、生产者、消费者C．消费者、生产者、分解者D．生产者、分解者、消费者-生物
• —Must I finish the work before five o'clock?—No, you_____.[ ]A. needn't B. mustn't C.
• -___________ I come in?-Sure. Come in, please.[ ]A. WillB. MayC. MustD. Need-九年级英语
• —Our class won the table tennis match. —Congratulations! You______proud of it.[ ]A. can be B. may be
• 在生态系统的分解者中，对生态系统物质循环起着不可替代作用的微生物是（）A．腐生性微生物B．寄生性微生物C．蓝藻D．硝化细菌-生物
• — _______ I watch TV? —Yes, you can watch the football game after you do your homework. [ ]A. May B.
• Can you see the book ?Yes , I__________.[ ]A. amB. doC. can-七年级英语
• 下列在生物圈中属于生产者的是（）A．牛B．水稻C．鸭D．猪-生物
• —Look at that man. He ________ Mr. Wang.—No. He ________ Mr. Wang. He has gone to Beijing. [ ]A. mus
• Cars, buses and bikes ______ stop when the traffic light is red. [ ]A. mustB. can C. may D. need-八年级
• —What are you going to eat supper?—I ____ have dumplings. [ ]A. may B. must C. need to D. can-八年级英语
• 请阅读下列信息并回答问题：“不必说碧绿的菜畦，光滑的石井栏，高大的皂荚树，紫红的桑椹；也不必说鸣蝉在树叶里长吟，肥胖的黄蜂伏在菜花上，轻捷的叫天子（云雀）忽然从草间直-生物
• 一个完整的生态系统，其组成成分包括（）A．食物链和食物网B．生产者、消费者和分解者C．阳光、空气和水等D．生物部分和非生物部分-生物