短语stop doing表示停止做某事。根据句意故填slowly

【题目】任务型阅读

Camels(骆驼) are amazing animals. They aren’t the most beautiful animals in the world. But they are certainly the most useful animals in the hot areas such as North Africa and the Middle East. They usually help people carry things. Now let’s learn more about camels.

There are two kinds of camels on the Earth. They are Arabian (阿拉伯的) camels and Asian camels. Arabian camels are dromedaries (单峰骆驼), but Asian camels are bactrians (双峰骆驼). An adult camel is about 2 meters tall and weighs about 500 kilograms. Its legs are long. And its feet are big and soft. Most of the camels can live for about 40 years, but they usually stop working when they are about 25.

Camels live alone in the desert (沙漠). They aren’t afraid of the hot and cold weather. They mainly eat grass, leaves and bushes. They can walk for more than 600 kilometers without drinking. They only need to drink water every six or eight days. But when there is water, they can drink up to 90 liters ( 升). Camels walk slowly. They don’t like running because it’s too hot. But if they need, they can run at 20 kilometers an hour.