单选题
Some animals sleep in wintertime because the weather can be very cold and it is difficult for them to find food. They can sleep for a long time (from autumn to spring). This kind of winter sleep is called "hibernation". If an animal moves about a lot, it needs food. Hibernating animals do not need to eat much because they are not moving about. Their hearts beat very slowly and they also breathe slowly. They find a place that is sheltered from bad weather and they are out of danger. Their body fat keeps them live and warm. Some animals, such as bears, may wake up from their hibernation on warm winter days and then quickly go back to sleep again when they see the snow is still thick on the ground. When the weather becomes warmer in spring, the animals wake up for food.
单选题
Why do some animals sleep in wintertime?
【正确答案】
A
【答案解析】[解析] 根据第一段第一句可知因为冬天天冷无法找到食物，很多动物就会冬眠，答案为A。
单选题
What does the word "hibernation" in the first paragraph mean?
【正确答案】
B
【答案解析】[解析] 前边讲了动物们由于冬天冷很难找到食物而会睡很长时间，所以应是冬眠，答案为B。
单选题
Why don't animals need food when they sleep is winter?