能量在食物链的流动过程中被多种生物逐步______，生态系统中的植物必须不断的从外界__________________，才能保证______的正常生活．因此______是生态系统的基础．与能量相比_

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• The girl _____ of medium build and_____ blonde hair.[ ]A. is ; is B. has ; hasC. has ; isD. is ; has
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• 校园内郁郁葱葱的樟树，在生态系统中属于（）A．生产者B．消费者C．分解者D．非生物部分-生物
• Chris Lee won the _________ for the best singers in 2009 Asia Song Festival. A．gradeB．resultC．prizeD
• Tom would rather _________than _________. A．stay at home , go outB．to stay at home , to go outC．to s
• The book_____ be jim’s because his name is on it.A. cant B. must C. can’t-七年级英语
• We usually ________CCTV news at 7:00 in the evening.A．watchB．watchesC．is watchingD．are watching-七年级英
• 以下关于能量在食物链中流动的叙述，正确的是（）A．从绿色植物流向植物性动物B．从太阳流向绿色植物C．从肉食性动物流向植食性动物D．从肉食性动物流向绿色植物-生物
• 阳光上的玻璃缸里有水草，养着各种观赏鱼，这个密封的玻璃缸就是一个（）A．生物圈B．生态系统C．非生物D．各种生物的群体-生物
• 如图为生产者、消费者、分解者之间的关系示意图，分析后请回答：（1）图中甲、乙、丙分别代表______、______和______．（2）在乙、丙、丁三类生物中，数量最多的是______，所含能量-生物
• 句型转换。①Tommy'sEnglishbookisonthetable.（改为否定句）Tommy'sEnglishbook_____ _____onthetable.②Mybas
• 用be的适当形式填空。1.These _____ myapples.2. Where_____yourchair?3. They_____inmybag.4. _____ theyunderthech
• —Let's play football after school. —That ______ good. [ ]A. smells B. sounds C. listens D. feel
• I'mgoingtoXi'anforaweek.That_____nice. [ ]A.listensB.soundsC.hearsD.looks -七年级英语
• — _______ your brother short?—No , he ______of medium height.[ ]A. Is;isB. Is;hasC. Has;hasD. Has;is
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• I’m not feeling ______, I _____ see a doctor.A good; will have to B. good; mustC. well; will have D.
• My mother and I _______going to watch TV this evening.A．areB．isn’tC．isD．am-七年级英语
• 如图为一个水域生态系统的示意图，请据图回答问题：（1）藻类是生态系统中的______，因为它们能够通过______制造有机物；大鱼和小鱼是生态系统中的______．（2）这条食物链中，生物-生物
• 分解者在生态系统中占有重要的地位，这主要是因为他们（）A．是实物的来源B．能释放氧气C．能净化空气D．能将动植物遗体分解为无机物-生物
• －Hi, Tom. Is this your dog?－No, it’s Cathy’s. _________ is at home now. A．MineB．MyC．HersD．Her-八年级英语
• 用括号内所绘词的适当形式填空。1.Those_____(be)hersisters.2.Theirgrandmother_____(be)JaneKing.3. — _____(be)theyLiPi
• Some oranges____in the bag. Some beef_____ on the table.[ ]A. is;isB. are; areC. are;isD. is; are-七年
• Where_____ the lions _____? [ ]A. does; fromB. does; come fromC. is; fromD. are; from-七年级英语
• 单项选择。The teacher asked," _____ everyone here?" [ ]A. Am B. Are C. Is D. Do -七年级英语
• 你的应变能力怎么样?用括号里所单词的适当形式填空,自己检验一下吧!1.I ___ (will )like to buy a tree.2.Please put these ____(photo) on
• This book _______ Lucy’s . Look! Her name is on the book cover（封面）.A．must beB．may beC．can’t beD．must
• 在一个生态系统中最不稳定的成分是（）A．高大乔木B．低矮灌木C．细菌、真菌D．大型动物-生物
• My brother likes playing ____ football, but he doesn’t like playing ___ piano.A．the; aB．the, theC．/;
• 下图示我国南方的一种新型的“桑→蚕→气→鱼”农业模式，该模式将蚕沙（蚕粪）、人畜粪便、枯枝败叶等投入沼气池发酵制成沼气，用沼渣喂鱼及为桑树施肥，获得了鱼、蚕、桑、气的全-八年级生物
• 用be的适当形式填空。①— _____thoseyourpencils? — Yes, they____.② I_____WangYun. MyQQnumber_____8055725.③These_
• 请你参照右图制作一个生态瓶，探究生物在一个密闭的生态系统中如何生存．制作方法是：将小鱼2条、小田螺4只和一定数量的水草一起放入盛有水的密封的广口瓶中．瓶底应放置一些沙-生物
• He is ______ outstanding student from ______ university in America. A．a; aB．a; anC．an; aD．an; an-八年级
• When he ________young, he________ a good kid.[ ]A. is; isB. was; wasC. is; wasD. was; is-七年级英语
• She _____ of medium height with short hair.[ ]A. is B. has C. does-七年级英语
• He asked me if I ______ mad ______ him. [ ]A. am; at B. was; at C. was; to D. am; to -八年级英语
• The yellow coat ________belong to Linda because nobody likes yellow except her. A．can’tB．mayC．mustD．
• I ______ it everywhere, but I didn’t _____ it. A．looked for, looked forB．looked for, find C．found, l
• Tina_________wait _________ see her parents .A．can; forB．can’t; forC．can; toD．can’t; to-九年级英语
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• ____________和____________是生态系统的重要功能。生态系统要完成这些功能是沿着________和________进行的。-八年级生物
• 下列是草原生态系统的食物网示意图，请据图回答：（1）该生态系统的生产者是______，直接以植物为食的消费者是______，没有表示出来的成分是______．（2）该食物网有______条食物链-生物
• You didn’t have breakfast. You ________ be hungry now.A．mustB．can’tC．couldD．might-九年级英语
• It _________ rain this afternoon, but I am not sure.A．willB．canC．mustD．may-九年级英语
• Frank is my pen pal, he _____________ Sydney, Australia.A．livesB．fromC．comes fromD．be from-八年级英语
• Listen to the music. It _______ interesting. [ ]A. sound B. listen C. sounds D. listens -七年级英语
• —Must I take the medicine every day?— No, you______.A．must notB．may notC．haven’tD．needn’t-八年级英语
• My teacher ______ a little bit heavy.[ ]A. isB. has C. there is-七年级英语
• I have two sisters. One is a teacher, ____ is a singer. .A．otherB． anotherC． the otherD． others-八年级英
• 生态系统中，完成物质循环的两个关键性成分是（）A．生产者和消费者B．生产者和分解者C．生产者和非生物成分D．消费者和非生物成分-生物