How airplanes fly?

People {#blank#}1{#/blank#} (try) for a long time before they invented a {#blank#}2{#/blank#} (success) "flying machine". Now there {#blank#}3{#/blank#} (be) so many {#blank#}4{#/blank#} (plane) in the sky.

    An airplane {#blank#}5{#/blank#} (fly) because of the upward force(力量) of {#blank#}6{#/blank#} (move) air against its wings(翼). To get that moving air, it needs something {#blank#}7{#/blank#} (push) it forward—like a motor-driven propeller(螺旋桨) or a jet engine(喷气发动机). You can fly a kite if there  {#blank#}8{#/blank#} (be) enough wind to hold it up. An airplane is like a kite with such force!

    More and {#blank#}9{#/blank#} (many) young people are getting to like making model planes now. How about you? Are you interested in it after {#blank#}10{#/blank#} (read) this article?

    China has decided to stop the use of free plastic bags. Supermarkets, shops and outlets(经销店) in China can't offer plastic bags any more.

    Every year, people use too many plastic bags. They throw them here and there after they have used them. The government has done its best to deal with them but failed. While we offer quick service（服务）to customers, the plastic bags pollute water, earth and air, and they waste the oil. The government asks people to go back to carry cloth bags and use baskets when they go to buy something. The cloth bags and the baskets can be used again and again.

    Many months have passed. The environment has been improved a lot.

      Information Card

    Humans can't stop natural disasters because we can't stop the power(力量) of nature.

    For example, a flood comes when there is too much water on the land. Sometimes, it can come after a big rainstorm at sea. Then too much sea water comes onto the land. Fast moving flood can hurt us. It can also hurt our homes. We can't stop the water from coming, but we can try to stop the water by making a wall with sandbags. Sometimes, the sandbags help stop the water. Sometimes they don't.

    An earthquake happens where land moves. The land goes up and down and all around. The land shakes. We may be hurt by things that fall down in an earthquake. Falling things can start fires. We can't stop an earthquake from coming. We can try to make our homes strong in order to prevent them from falling down in an earthquake.

    A tornado(龙卷风) is fast air that goes around and around over the land. A tornado can pick up everything. It can break anything in the way. A typhoon is a big storm with fast moving wind and rain. It begins at sea and can come onto the land. Its fast winds can hurt us and our homes.

    We can't stop the power of nature, but we can go to places where we will feel safe.