The students were having their chemistry (化学)class. Miss Li was telling the children what water is like. After that, she asked her students, “What's water? ” No one spoke for a few minutes. Miss Li asked again, “Why don't you answer my question? Didn't I tell you what water is like? ”

    Just then a boy put up his hand and said, “Miss Li, you told us that water has no colour and no smell. But where to find such kind of water? The water in the river behind my house is always black and it has a bad smell.” Most of the children agreed with him.

    “I'm sorry, children,” said the teacher, “our water is getting dirtier. That's a problem.”

     Hello! I'm Li Lei. I have a new friend. He's friendly and funny. He can speak English and Chinese. He can do some kung fu. He can play ping-pong. I can play ping-pong, too. We can play together. I can swim, but he can't swim. Who is he? Can you guess? Let me tell you, he is Robin the Robot！

    Hello! I'm Victor.I have a bed, a desk, two chairs and a computer in my bedroom.My bed is small but very nice.It's blue because I like blue very much.My desk is big.It's white.You can see a computer and so many books on it.I do my homework here.I have two chairs.One is big and one is small.The big one is near the bed.The small one is near the window.I like my room.

    The air is everywhere around us. Air has no colour. We can't see it. When it moves, we can feel the air. Air is very important to our lives. People and plants can't live without it. If there was no air, there would be no life.

    Aeroplanes can't fly without air. The air holds up the planes. We can't make fire (生火) without air. If you cover (盖住) a burning (燃烧的) candle with a glass. It will quickly go out (熄灭).

    Sound spread (传播) through the air. Without air, we can't hear.