When the weather is hot, you go to a lake or an ocean. When you are near a lake or an ocean, you feel cold. Why? The sun makes the earth hot but it can not make the water very hot. Although the air over the earth becomes hot, the air over the water stays cool. The hot air over the earth goes up. Then the cool air over the water moves in and takes the place of the hot air. When it moves in, you feel the wind. And the wind makes you cool.
Of course, scientists can not answer all of our questions. If we ask, “Why is the ocean full of salt?” Scientists will say that the salt comes from rocks. When a rock gets very hot or very cold, it cracks (断裂). Rain falls into the cracks. The rain then carries the salt into the ocean. But then we ask, “What happens to the salt in the ocean?” The ocean does not get more salty every year. Scientists are not sure about the answer to this question.
We know a lot about our world. But there are still many answers that we don’t have and we are curious about.
1. The main idea of this passage is that ______.
A. people feel cool when they are near a lake or an ocean
B. scientists can explain many things, but not everything
C. scientists can explain everything about the ocean
D. the salt in the ocean comes from rocks
2. Now scientists know ______.
A. what makes people feel cool near a lake or an ocean in summer
B. everything about the ocean
C. what happens to the salt in the ocean
D. why the ocean does not get more and more salty
3. A rock cracks when ______.
A. rain falls B. it snows
C. it gets very cold D. it gets warm
4. People are always curious because ______.
A. they know nothing about the world
B. they know only a little knowledge about the world
C. there are many answers they don’t agree
D. there are many things they don’t know
5. Which of the following reasons is NOT mentioned in this passage?
A. Why do people feel cool when they are near a lake or an ocean in hot weather?
B. Why doesn’t the ocean get more salty every year?
C. Why is the ocean water salty?
D. Why do rocks crack?
BACDB
A. Profits enlarging B. Technology developing C. Education investing D. Benefits transferring E. Dominance disappearing F. A nation rising |
The following is an imaginary diary entry written by US president. This diary is part of Global Trends 2025, which was written by the US National Intelligence Council
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The
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The
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Global wealth and economic power will shift from West to East.
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The transition from old fuels to new will be slow, as will the development of new technologies that present feasible alternatives to fossil fuels or help eliminate food and water problems. All current technologies are inadequate, and new ones will probably not be commercially possible by 2025