题干

如果设计一个实验探究土壤的干湿程度对蚯蚓生活的影响,下列设计中错误的是(  )

A:设计甲(湿润土壤)、乙(干燥土壤)对照实验

B:在甲、乙两容器中各放入1条蚯蚓

C:甲、乙两容器中放入大小及生活状况均相同的蚯蚓各10条

D:甲、乙两容器都放在相同的环境中

上一题 下一题 0.0难度 选择题 更新时间:2017-11-17 11:05:09

答案(点此获取答案解析)

B

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                                                                                Swimming and English Learning
    Can you swim? Do you like swimming? Yes? Well, how can you learn to swim? I think the best way is to go into the water and learn. I'm afraid you'll never learn to swim just by reading books about swimming or looking at others swimming. It's the same with the English study. We must practice, practice and practice.
    Listening and speaking are very important for beginners. The children in English-speaking countries first listen to others. Then they try to imitate and speak. We can listen to English programs on radio. You may just understand a few words. It doesn't matter. Just be relaxed, try to catch every word.
    Somebody may be a good listener. But he dare not speak. He's afraid of making mistakes. You know we sometimes make mistakes when we speak Chinese. Don’t be afraid. We must be brave. If you really want to learn English well, you must try to speak with everyone so long as he knows English. Whether you know him or not is not important when there’s nobody to talk with, you can talk to yourself in English. It's interesting and also a good way to practice your spoken English. Remember, the more you speak, the fewer mistakes you'll make.
Reading and writing are more important for senior school students. First we must choose the books we’re interested in. A lot of reading will improve your language sense. This is the most important.
    Keep writing English diaries. We can also write English articles. You may even post them to English magazines. Don't be afraid of failure. Failure is the mother of success.
    Easier said than done. Well, let's do more practice from now on. I'm sure you'll learn English well in this way