题干

下列对各类生态系统特征的描述,正确的是:

A:森林生态系统动植物种类繁多,群落结构复杂

B:草原上生活着多种动物,其中主要是两栖类动物

C:引起海洋生物垂直分布的主要非生物因素是氧气含量

D:在自然生态系统中不一定有微生物存在

上一题 下一题 0.0难度 选择题 更新时间:2019-07-11 11:10:16

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A

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    Everyone has two personalities(性格)-- one is showed to the world and the other is secret and real. You don't show your secret personality when you're awake because you can control(控制) yourself, but when you're asleep, your sleeping position shows the real you. And the important position that best shows your secret personality is when you go to sleep.

    If you go to sleep on your back, you're a very open person. You usually believe people and you are easily influenced(影响) by new ideas. You don't like to make people unhappy, so you never show your real feelings. You're quite shy and you aren't very confident(自信的).

    If you sleep on your stomach, you are a person who likes to keep secrets. You worry a lot and you're always easy to be sad. You never want to change your ideas, and you are pleased with your life. You usually live for today not for tomorrow.

    If you sleep on curled up(蜷缩),you are probably a very nervous person. You have a low opinion of yourself and often don't want to be hurt, so you are very defensive(有戒心的). You're shy and you don't like meeting people. You like to be alone.

    If you sleep on your side, you usually have a well-balanced(平衡的)personality. You know your strengths and weaknesses. You're usually careful. You have a confident personality. You sometimes feel worried, but you don't often get unhappy. You always say out what you think, even if it sometimes makes people angry.