The  1  is getting colder, and soon winter  2  shorter. We live in warm houses and we  3  thick coats when we go outside. But 4  do animals stay warm in winter?

Adapt(适应)

    Some animals keep  5  in winter, so they must adapt to the changing weather.  6  warm, they may grow new, thicker fur in  7 autumn.

Migrate(迁徙)

    Some of the animals migrate. That means they travel to other places  8  the weather is warm or they can find food.

Hibernate(冬眠)

    Some animals hibernate for part or  9  of the winter. These animals usually find a cave or a hole under the ground to spend their winter. The body temperature of the animals drops, their heart beats more slowly and they breathe  10  .

The US public uses about 50 billion water bottles a year and most of those {#blank#}1{#/blank#} bottles are not recycled, according to Elizabeth Royte's book Bottlemanid: How Water Went on Sale and Why We Bought It.

More than $100 billion is spent every year on bottled water in the U.S. in many developing countries where there isn't a safe {#blank#}2{#/blank#} of tap water, bottled water is the only choice.

In the US, tap water is controlled by the government and often {#blank#}3{#/blank#} for dangerous substances(物质). Each American drinks 79 litres of bottled water per year {#blank#}4{#/blank#}. The bottled water industry is so successful that it has outpaced milk, coffee, and juice in the number of gallons of drinks sold – putting it behind only beer and soda.

    The computer is fast, and never makes a mistake, while people are too 1 and full of mistakes sometimes. That's what people often say when they talk about computers. For over a quarter of a century, scientists have been 2 better and better computers. Now a computer can do a lot of everyday 3 wonderfully. It is 4 used in factories, hospitals, post offices and airports. A computer can report, decide and control in almost every field. Many computer scientists are thinking of making the computer “think” like a man. With the 5 of a person, a computer can draw pictures, write music, talk with people, 6 chess, recognize voices, translate languages and so on. Perhaps computers will one day really think and feel. Do you think the people will be 7 when they find that the computer is too clever to listen to and serve the people? No, people will make 8 use of the computers in the future. Man is always the master of the computer. The computer 9 only with the help of man. It cannot take the 10 of man.

    The universe is really mystical(神秘的）.Scientists have done lots of study about it but there is still much they haven't discovered.

    Scientists think that there1life on the earth for hundreds of millions of years. However, we have not found life on any other planets2.

    There are eight planets going around the sun. The earth is one of them. There are humans, animals, and many other kinds of life on the earth. There is water and air, too. And compared to other planets, the earth is not too3or too cold. None of seven other planets has an environment like that of the earth.

    The sun and its planets are called the solar system, and our solar system is a small part of a4larger group of stars and planets, called the Galaxy or the Milky Way. There are5stars in the Galaxy, and our sun is only one of them.

    Scientists have also discovered many other galaxy in the universe. They are very far away and their light has to travel for many years to reach us. So 6is the universe? It is impossible to imagine.

    Scientists have sent spaceships to the planet Mars to7photos. They have even sent spaceships to travel outside 8 .However, no spaceship has traveled9to reach other stars in our Galaxy.

    When we see stars twinkling(闪耀）in the sky at night, we may think a lot:10so many stars in the universe, are we alone, or is there life out there in space? Have there been visitors to the earth from other planets? Why has no one communicated with us? We do not know the answer...