今年是祖国母亲60岁生日，小明、小敏、小新商量要在国庆前夕给祖国母亲献礼，决定画5幅国画表达大伙的爱国之情。小明说：“我来出一道数学题：把剪5幅国画的任务分配给3个人，每人至少1幅，有多少种分配方法?”小敏想了想说：“设各人的任务为x、y、z，可以列出方程x+y+z=4。”小新接着说：“那么问题就成了问这个方程有几个正整数解。”现在请你说说看：这个方程正整数解的个数是(       )

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                                                                                    Keeping Healthy

    (Kangkang's father, Dr. Li, is giving a talk about health to the students.)

    You need to have healthy eating ____ (习惯). Breakfast gives you enough energy for the morning. So don't go to school ____ it. Fruit and vegetables are good ____ your health, but fast food, like potato chips, will make you ____ /fæt/ and unhealthy. So eat the right food to keep you healthy.

    Playing sports can also help you keep fit. But sometimes accidents can ____/'hæp(ə)n/, so try to stay safe when you play them. It's necessary for you to learn about first aid. Then you can help yourselves or others if an accident happens.

    Happiness is important for your ____(健康). It is the best medicine. When you are ill, try to be happy and you'll feel better. ____ ____ ____ ____(另一方面), you may feel ill if you are always unhappy. So, be happy to be healthy.

    You must stay away from smoking and drinking. Many students think it's cool to smoke and drink. But they don't know smoking or drinking can cause many illnesses. You should ____ ____ ____(拒绝) smoking and drinking.