肉类和鸡蛋的价格比粮食和蔬菜高，从生态学的观点看，这是由于[]A．饲养动物麻烦，时间长，投资大B．动物性食品营养价值高C．食物链延长，能量流失多，动物性食品成本高D．栽培植-八年级生物

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• I __________ dance but I___________ dance well.[ ]A. can; canB. can; can'tC. can't; canD.
• 下图是自然界碳循环的简图，图中甲、乙、丙各代表[]A．生产者、分解者、消费者B．消费者、分解者、生产者C．分解者、生产者、消费者D．生产者、消费者、分解者-八年级生物
• If I went to the moon,I _____ bring something unusual back to school.[ ]A.willB. canC. wouldD. shall
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• —Could I use your pen? —Of course, you _______.[ ]A. must B. may C. can -九年级英语
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• —Let's go to the movies tonight.—Sorry.I__ . I have to help my mother wash clothes.[ ]A. mustn&
• —Where's my watch? I can't find it anywhere.—It _ _ in your bag or under these books.[ ]A.
• 古书《说苑．正谏》中有这样一段记载：“园中有树，其上有蝉，蝉高居悲呜，饮露，不知螳螂在其后也；螳螂委身曲附欲取蝉，而不知黄雀在其傍也；……”这是比喻社会现象的寓言，但却反-八年级生物
• —He is tired now.He_____ stay at home and have a rest.—Thanks, doctor.[ ]A. has toB. maysC. needD. c
• —Could I borrow your dictionary?—Of course I _____.[ ]A. canB. mustC. shouldD. have to-八年级英语
• Henny _________be at home now because he phoned me from the school just now .[ ]A.mustn't B.isn
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• Return home quickly. Your parents _____ be worried about you now.[ ]A. canB. may C. must D. could-九年
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• 小华同学说：“爷爷讲在他小时候，村边的小河里有许多鱼、虾，稻田中有不少黄鳝和泥鳅。现在河里和稻田中几乎没有鱼、虾了。”这是什么原因呢？（1）请对上述情况做出假设：_______-八年级生物
• —Is this pair of shoes Jim's? —It _his.They're too big for him.[ ]A. might be B. can'
• —I still have a toothache. —Oh, sorry, the medicine didn't work, so you ________try another kin
• 研究生态系统的能量流动，可帮助人们合理地调整生态系统中能量流动的关系，使能量_________地流向对人类最有益的部分。-八年级生物
• I_____play the guitar.It's too difficult. [ ]A. canB. can't C. doesn't-七年级英语
• —You see, a man is cutting a tree on the moon. —It _________ be true. The teacher says there is no a
• 根据句意从方框中选用合适的词组，并用其适当形式填空 fix up take after hand out clean up call up 1.The teacher __________ all t
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