在做光合作用实验时，要用黑纸片遮盖住天竺葵叶片的一部分，其原因是A．便于观察B．便于实验C．对照实验D．便于观察与实验-七年级生物

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• —How about going shopping this weekend , Peter?—Sorry. I prefer _ rather than _ .[ ]A. to stay at ho
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• 调查池塘生态系统，除了记录本和笔之外，下列哪一选项所带工具是最合适的？A．铲子望远镜照相机B．网兜放大镜玻璃瓶C．铲子显微镜玻璃瓶D．网兜显微镜照相机-七年级生物
• You look tired. You need ________ a good rest. [ ]A. has B. have C. to have D. having -八年级英语
• The girlforgot _________ the light when she left the room.[ ]A. to turn offB. turning offC. off D. t
• 根据你的调查，以下归纳正确的是[]A．黄瓜、虾、蝗虫为陆生生物B．鸡、鸭、猪为家禽C．小麦、水稻、海带是农作物D．鲫鱼、蟹、水绵为水生生物-七年级生物
• 探究某一问题成功的关键是A．作出符合科学事实的假设B．提出有研究价值的问题C．制定出恰当的科学探究计划D．写出高水平的论文-七年级生物
• They told the boy _ dolls in the street.[ ]A. not to sell B. to sell notC. to not tell D. don't
• Who is always the first one_____ class?[ ]A. to come to B. come toC. comeD. to come-八年级英语
• It will take the workers half a year_____ the work.[ ]A. finishB. finishing C. to finish D. finishes
• -Julia Morgan, the famous movie star, plans _________ a relaxing vacation in Spain.-I hope he will h
• If you want to learn English well, you need __ it as much as possible.[ ]A. practice speaking B. to
• 下列图示中，酒精灯使用不正确的是-七年级生物
• 如图所示，某同学为验证空气中含有少量二氧化碳，将大针筒内的空气一次性压入新制的澄清石灰水，发现石灰水没有变化。据此，你认为该同学应该A．继续用大针筒向澄清石灰水压入-七年级生物
• Some of them would like_____some tea rather than _____some coffee. [ ]A. to have; to have B. having;
• 用所给词的适当形式填空。1. Our class is organizing a talent show________( raise)money for thecharity．2. I had a
• 在探究“植物对空气湿度的影响”时，下列做法中不正确的是A．测量裸地、灌丛的湿度时，都应该把干湿计放在地上B．如果裸地上有水洼，测量时不能把干湿计放在水洼边C．对于同一地点-七年级生物
• 下列关于调查的叙述，不正确的是A．人口普查也是调查B．森林资源的清查是调查C．要对调查的对象逐个进行D要对调查的结果进行整理和分析-七年级生物
• 生物小组4名同学分别采用下列四种途径收集资料，其中哪种途径不科学?A．去图书馆查阅书刊报纸B．上网搜索C．请教科学家D．从小说中查找-七年级生物
• It’s bestBeijing in autumn,I think.[ ]A. for visitB. to visitingC. to visit D. for a visit-八年级英语
• 下面是进行探究活动要遵循的一般步骤，按照先后顺序排列正确的是①实施计划②作出假设③制定计划④得出结论⑤提出问题⑥表达和交流。A．⑤②③①④⑥B．①③④⑤②⑥C．⑤④③②①⑥D．②③④①⑤⑥-七年级生物
• —Could you ask your father in our school?—Sure.[ ]A. don’t to smoke B. not smoke C. not to smoke D.
• —Why do you want to learn French?—I think it is fun_____ language after English. [ ]A. to learn a B.
• 实验应在一切条件都相同的情况下重复做几次，并取其平均值，以尽是减少误差的影响。（）-七年级生物
• 科学探究的过程：提出问题→→制定计划→→得出结论→表达交流-七年级生物
• Now most Chinese families in the country have their own houses ________[ ]A. to live B.living C. liv
• 动物与人们的生活息息相关，既有有利的一面，也有有害的一面。苍蝇、老鼠人见人厌，你能发现它们有利的一面吗?-八年级生物
• 关于科学观察的叙述中，错误的是A．观察时要积极思考，多问几个为什么B．科学观察要有明确的目的C．观察时要全面、细致和实事求是D．科学观察都不需要测量-七年级生物
• —I forget ______ the window when I left. —It doesn’t matter. Let me help you. [ ]A. close B. closing
• 实验中如果结果和假设不符合，正确的处理方法是（）A．修改结果，使其与假设相符B．依据实验结果下结论C．修改实验过程，使其与假设相符D．修改假设，重新做试验-七年级生物
• The doctor told the boytoo much junk food because he is really fat.[ ]A. don’t eatB. not to eat C. e
• 科学探究的正确顺序是①提出问题②制定计划③作出假设④实施计划⑤得出结论⑥表达和交流A．①②③④⑤⑥B．①③②④⑤⑥C．③②①④⑤⑥D．②⑥①④③⑤-七年级生物
• 尝试探究（6分）桃花鱼为腔肠动物门水螅纲的一个小类群，栖息于淡水中，因其形状酷似桃花而得名，其中文名是桃花水母。生长于三峡库区姊归县归州镇鸭子滩的桃花水母是极为稀有-七年级生物
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• 图中是显微镜下观察到的几种微小生物，据图陋答问题。ABCDE（1）这几种生物在身体结构层次上的共同特点是__________________（2）试根据细胞结构的特点，将图中生物进行分类。①属-七年级
• He was too old ___ by himself.[ ]A. walk B. walking C. to walk D. not to walk-八年级英语
• I can't go home now because I forgot_____ umbrella_____ me.[ ]A. to bring; toB. bringing; toC.
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• 海鲜馆里有一道菜叫“西施舌”（一种贝类）炒“九层塔”（一种香料植物），媒体报道九层塔中含有黄樟素，小明看了报道以后：①小明猜测微量黄樟素会导致癌症②于是，他准备了两组老鼠，-八年级生物
• 珍·古道尔4岁半时，很想知道母鸡身上哪里有一个可以让鸡蛋“钻”出来的洞。她最好采用什么方法？A．测量法B．观察法C．实验法D．调查法-七年级生物
• He chose__ a red shirt, because she likes red.[ ]A. to buyB. buyC. buyingD. bought-八年级英语
• That is all they can do _____ the poor students in that village school. [ ]A. help B. to help C. hel
• This is the best time ________ books.[ ]A. readingB. readC. to readD. reads-八年级英语
• I'm really happy___ the tickets.[ ]A. havingB. have C. has D. to have -八年级英语
• 在科学探究过程中，为了保证实验的科学性A．不需要设置对照实验，太麻烦B．只需要一组实验就可以了C．对照实验可有可无D．需要设置一组对照实验-七年级生物
• 用所给词的适当形式填空。1. I can't find the museum. What should I ___________ (do)?2. I need some more mone
• What are you going _____ when you grow up?[ ]A. beB. to beC. do D. does -八年级英语
• We have worked for three hours. Now let's stop _____ a rest. [ ]A. had B. have C. to have D. ha
• 学习生物学的方法很多，要了解本市名贵珍稀树木的种类和分布，我们采用的最佳方法是A．观察B．探究实验C．调查D．资料分析-七年级生物