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⑴天气对我们的影响。(如：天气好坏会影响人的心情；在晴天人们可以外出，在雨天可能只好待在家里)

⑵你喜欢什么样的天气，为什么？

Man and weather

    More than millions of years ago, there were deserts. Now about one fifth of the Earth's surface  (be) deserts. The size of the world's deserts keeps  (change). Deserts can be hot or cold. The Australian Desert is a hot desert, while the Gobi Desert is a cold desert. A desert is a very dry land and there is hardly any rain. The Sahara Desert in Africa receives less than 1.5 cm a year.  it doesn't rain very often in deserts, sometimes even for years, there can be heavy rain suddenly. Because they are dry, deserts have wide changes in temperature each day. When the Sun goes up, it is very hot, even hot enough  (fry) an egg on the ground. At night, the heat that  (receive) by the ground during the day disappears  (quick), and then it gets  cold that water would turn into ice. Because  the change, living in the desert is very difficult. Man can make deserts, but man can also stop  (they) from getting larger and larger. Planting trees can prevent the sand from  (spread).

—It was terrible! It rained a lot during my stay.

—Many scientists are working hard to find them. But there's still no good news.

—OK. Be careful! The traffic is quite busy now.

—No problem.

    The undersea world is very beautiful. Now more and more people want to dive in the sea to find the secrets there.

    There are many strange animals in the sea. Some are as large as a school bus. Many sea animals give out light in the dark. Many fish have no eyes while some have big eyes. A few have eyes on one side of their heads.

    During the day, there is enough light. Everything under the sea looks green and blue. But the deep sea is not an easy place to stay in. So you must be very careful when you dive in deep water. It's cold, and it's dark too. The deeper it is, the less sunlight there is. At about 3,000 feet deep, there is no light at all.

    Besides the cold and the darkness, deep-sea animals face a third danger-other animals! They must find food to eat. Many animals eat plants. However, some animals eat meat. This means these sea animals have two big jobs. They need to find animals as food, and they have to try not to become other animals' meal.

—Sorry. I won't make any noise from now on.