In winter, the weather gets colder. There is snow on the ground. People live in warm houses and wear heavy coats outside. But what happen to the animals?

冬天，天气转冷，雪覆盖了大地。人们呆在温暖的房子里，出门也穿上了厚重的外衣。但是动物又会怎样呢?

  
Some animals sleep all winter. It is a very deep sleep called hibernation (冬眠). The animals’ body temperature drops, and its heartbeat and breathing slow down. These animals get ready for winter by eating extra food and storing it as body fat (脂肪). They need little or no food while hibernating. Bears and chipmunks （金花鼠） hibernate. So do frogs, snakes and even some bugs.

Tip: 动物越冬的方式之一为冬眠。当动物冬眠的时候，体温降低，心跳和呼吸也减慢。有的动物几乎整个冬天都处于睡眠状态，只消耗体内贮存的脂肪来补充能量；而有的动物则会中间醒来吃些秋天贮备的食物。
 
 
 
Some birds fly south for the winter. We call this migration. Some of them travel in large flocks. For example, geese fly in noisy, “V”-shaped groups. Other kinds of birds fly alone. They go to a warmer place to find food. Other birds stay here all winter. We can help by feeding them. Besides, some fish and a few mammals (哺乳动物) migrate too, like some bats and whales.

Tip: 动物越冬的方式之二为迁徙。这种行为在鸟类中居多。它们通常会成群结队地飞往南方过冬，如大雁。此外，一些鱼和哺乳动物也会在冬天到来的时候进行迁徙。如一些蝙蝠和鲸类。


 
Other animals stay active in winter. They must adapt (适应) to the changing weather. It is hard for them to find food. They gather extra food in the fall and store it to eat later. To keep warm, some animals may grow new, thicker fur in the fall and live in holes in trees or under the ground in the winter. Deer, squirrels and rabbits stay active.

Tip: 另外还有些动物必须要适应天气的变化。它们会提前贮备食物，有的会长出又厚又长的毛或者干脆就躲在树洞中和地下保暖。如鹿、松鼠，兔等。