题干

薇甘菊是多年生藤本植物,在其适生地能攀援、缠绕于乔灌木,重压于其冠层顶部,阻碍附主植物的光合作用,继而导致附主死亡.因此,薇甘菊是世界上最具危险性的有害植物之一.科研人员研究了薇甘菊不同入侵程度对深圳湾红树林生态系统有机碳储量的影响,结果如表.请分析回答:

有机碳含量/t•hm﹣2

未入侵区域

轻度入侵区域

重度入侵区域

植被碳库

51.85

50.86

43.54

凋落物碳库

2.01

3.52

5.42

土壤碳库

161.87

143.18

117.74

总计

215.73

197.56

166.70

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                                                                                               C

    As you touch people and objects throughout the day, there are germs(细菌) on your hands. In turn, you can make yourself ill with these germs by touching your eyes, nose or mouth. Although it's impossible to keep your hands germ-free, washing your hands is good for you. It limits the chance of getting sick and is one of the best ways to avoid(避免) getting sick and spreading illness. Staying healthy can make you feel happier.

    Hand washing requires only soap and water, but do you really know when and how to wash your hands? The following information may be useful for you.

    When to wash your hands

    Always wash your hands before:

    ▲Preparing food

    ▲Eating

    ▲Giving medicine

    ▲Touching a sick or injured person Always wash your hands after:

    ▲Preparing food

    ▲Using the toilet

    ▲Touching an animal or animal toys or waste

    ▲Touching a sick or injured person

    Of course, it's also important to wash your hands whenever they look dirty.

    How to wash your hands

    It's generally best to wash your hands with soap and water. Follow these simple steps:

    ▲Wet your hands with running water.

    ▲Use soap.

    ▲Wash your hands for at least 20 seconds. Remember to wash the hands carefully, including the backs of your hands, wrists, fingers and fingernails.

    ▲Dry your hands with a clean towel.