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    Camels are large animals living in dry areas. There are two species of camels; the Arabian camel with a single hump(驼背) from the dry desert areas of West Asia, and the Bactrian camel with two humps from Central and East Asia. Camels are over 7 feet tall and weigh over 1,600 pounds. They will live up to 40 to 50 years. Most camels are domesticated(驯化) and fed by people. Camels are plant-eaters．

    Camels are very strong animals with wide, padded feet. They have thick leathery pads on their knees and chest. Camels have nostrils(鼻孔)that can open and close, protecting them from the desert environment. Bushy eyebrows and two rows of long eyelashes protect their eyes from sand. Their mouth is extremely tough, allowing camels to eat thorny(带刺的)desert plants. Their widened feet help them move without sinking into the sand. Their thick coats reflect sunlight, and also protect them from the intense heat from desert sand. Their long legs help by keeping them further from the hot ground．

    Camels can go without food and water for 3 to 4 days. They do not store water in their humps as is commonly believed．The humps are actually a container of fat. Camels are incredibly well-adapted to their environment. When conditions heat up, camels can increase their own body temperature, which prevents sweating and therefore water loss. They may not sweat at all during the day．

    Camels are sometimes called“ships of the desert”because people ride them around the hot, dry deserts of the world．However, the number of camels is becoming smaller for various reasons．

C

    "Tom? Are you in bed yet?" called Mrs. White. There was no answer. Mrs. White put down her book and went to her 14-year-old son's room. Tom was sitting in front of a bright computer screen on which a motorbike was running fast.

    "Oh, Tom. You're still playing on that computer game. You must stop now, because it's half past eleven. If you don't go to bed soon, you'll be very tired tomorrow." Said Mrs. White.

    "But I've nearly won the game." Tom said to Mrs. White. She could see the excitement on his face. She sat beside him.

    "You're always playing on the computer. You spend more time on this machine than on your homework."  

    Today more and more families have computers. Parents hope computers can help their children improve their study at school. But many of their children use computers to play games, listen to songs and watch videos instead of studying. We often see that computer net bars are crowded with people, especially young boys. They spend a lot of money competing with the computerized machines. The more they lose, the more they want to win. The result is that they don't want to work or study.

    In some countries, even scientists hate computers. They say computers cause millions of people to lose their jobs or cause them a lot of trouble. Computer game addiction(瘾) is a serious problem in social life. Something should have to be done to solve the problem.