Arctic fox(北极狐) is a kind of small fox that lives in the Arctic. It grows about 50 centimeters long, not including its tail, 30 centimeters tall and weighs from 3 to 7 kilos.
   The Arctic foxes are white or blue in color. The white ones are white in winter, but grey-brown in summer. The blue ones are blue-grey all year round. The Arctic foxes have long, thick hair that is called fur. And the long fur covers their whole bodies, including both their cat eyes and rabbit feet, to keep them warm in the low temperature in the Arctic.
   The Arctic foxes feed mainly on birds, birds' eggs and other small animals. Teamwork is the way they look for food, and they don't like to do that alone.
   Baby Arctic foxes are very lovely. They don't open their eyes until a week after their birth. For the first half of the year, their parents offer them food. They begin to look for food on their own when they are about six months old. The next year they can live alone.
   Today, the number of the Arctic foxes is becoming smaller and smaller, because people kill them for their fur to make beautiful coats for money. Something must be done to protect the Arctic foxes.

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    What do you think is the most important invention? The TV? The printing? The telephone? Or the computer? A report show that they are not the only important invention. Here are three other important inventions.

    One of the simplest inventions is the toilet(厕所). Before toilets, waste ran into rivers from people's houses. Illness were common in big cities, and it was often difficult to find clean drinking water.

    Animal food is another important invention. Before the invention, most animals were killed every autumn because there was not enough food for them in winter. After hay(干草) became a kind of common animal food, animals could live through the long winter.

    The third great invention is glasses. Glasses help people read, write and do "close work" after the age of 45. Without glasses, the world would be difficult for the people above 45.