根据生态学原理，要使能量流经食物链的总耗量最少，人们应采取下列哪一种食物结构？[]A．以禽类、蛋类为主B．以淡水养殖的鱼虾为主C．以谷物和植物蛋白为主D．以猪肉等家畜的肉类-八年级生物

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• Does Jack want to_____ the first one to get to the top of the mountain? [ ]A. to B. to beC. being D.
• 如图为生态系统各成分之间的相互关系，据图分析，回答下列问题：（1）图中生态系统中的生产者是______．（2）图中虫和鸟是生态系统中的______．（3）如果人们大量捕杀鸟，使鸟的数量减-生物
• 生态系统中的非生物部分是指阳光、______、水．-生物
• 下列关于生态系统成分的表述中不正确的是（）A．植物是生态系统的生产者B．动物直接或间接地以植物为食，是消费者C．细菌和真菌是生态系统中的分解者，也是消费者D．阳光、空气、水-生物
• He has poor _______, so he can’t see the words on the blackboard clearly.A．smellB．tasteC．hearingD．ey
• The factory ______ its waste into the river, but now it deals with the waste in a new way.A．used to
• The art exhibition is really worth _______，and you’re sure to learn lot from it. A．visitB．to visitC．
• For everyone’s safety，we _______ a1ways remember the law against driving after drinking.A．couldB．sho
• - Mr Jackson, __ we go rock climbing? m Yes, but you must use ropes.A．mustB．shouldC．needD．can-九年级英语
• 生物圈中的生产者是（）A．动物B．人类C．菌类D．绿色植物-生物
• Maybe he can ____ in their basketball team. [ ] A. is B. be C. are -七年级英语
• 用Be 动词的适当形式填空。1. Jack ______ late for school yesterday, for he ______ ill. 2. I______in the same sch
• —What_____he like?—He's really friendly and kind.[ ]A. can B. does C. are D. is -八年级英语
• Oh, the milk _____ strange. Do you think it' s OK to drink? [ ]A. was tastedB. tastedC. is tast
• 非生物物质为整个生态系统的生物生活提供_____和_____。-八年级生物
• 下列各项中，属于分解者的是（）A．水族箱中的金鱼藻B．蚊子C．墙角的苔藓D．朽木上的蘑菇-生物
• 生态系统中的生产者主要是指（）A．绿色植物B．各种动物C．腐生细菌D．各种真菌-生物
• —You look so tired. —Yes. The loud noise upstairs stopped me the whole night.A．sleptB．to sleepC．fell
• Mr Chen __________ his mobile phone to the shop because it can’t work at all.A．need to returnB．needs
• That __________ our English teacher.[ ]A. maybe B. may beC. mayD. be-八年级英语
• If your mother were here, she ______ allow you to surf the Internet for so long.[ ]A. won't B.
• The boy _____healthy_____he doesn't like to exercise. [ ]A. doesn't, so B. isn't. so
• 根据对这幅图的观察，请你回答以下两个问题：（1）请用箭头把它们表示出来．（2）在这个小型生态系统中，草是______者，所有的动物是______者．食物链彼此互相交错，构成了______．这-生物
• There is going to ______ a basketball match on the playground this afternoon. [ ]A. has B. have C. b
• 一般的说生态系统中数目最少的是（）A．植物B．草食动物C．肉食动物D．细菌和真菌-生物
• 如图是自然界碳循环的简图，图中的甲、乙、丙各代表什么（）A．甲为生产者，乙为分解者，丙为消费者B．甲为消费者，乙为分解者，丙为生产者C．甲为分解者，乙为生产者，丙为消费者-生物
• I think swimming in the pool with friends ______ very interesting. [ ]A. has B. have C. is D. are -九
• You may get lost easily in big cities like Beijing you have a map or a guide.A．unlessB．ifC．whenD．unt
• —Do you know ?—I’m not sure, maybe he is an artist.A．who is the manB．what is the manC．who the man is
• —No student ______ to eat snacks in our school. —But still there are some students breaking the rule
• He used to _______ in a village, but now he has been used to _______ in the big city.A．live; livingB
• The stories _____ boring. [ ]A. sound like B. sounds like C. sound-八年级英语
• 在一个以小麦为主要农作物的农田生态系统中，生长着杂草，生活着蚜虫、蜘蛛、田鼠、蛇等其他生物．据此请分析回答：（1）请你写出此农田生态系统中，小麦与其他生物之间两种关系-生物
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• The Greens _____ China for seven years. [ ]A. have come to B. have been to C. have come in D. have b
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• --- Listen! David is talking happily with his mother in the next room.--- It ______ be his mother. S
• His parents _____ teachers of English. [ ]A. is B. are C. 's D. 're -七年级英语
• 用动词be的适当形式完成句子。1.—______ Guo Peng your brother?—No, he isn't. 2. Anna and Alice ______ my good
• 用am , is , are 填空。 1. I_____ Kate. He_____ my brother. 2. —What _____ your name? —I _____ Sandy. 3.—
• 在一个相对稳定的生态系统中，数量最少的是（）A．植物B．草食动物C．细菌和真菌D．肉食动物-生物
• 如图是一个湖泊生态系统，请根据图回答：（1）此生态系统的生产者是______．（2）此生态系统的消费者是______．（3）在此湖泊生态系统中，肯定存在没有表现出来的生物是______．它们在-生物
• —Look at that girl! Is it Susan?—No, it _______ be her. She has gone back to her hometown.A．mustn’tB
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