题目

完形填空Some animals, such as tigers and lions, are called wild animals. like sheep and dogs are called domestic(家养的) animals. These animals are very differentone another, but we can divide them into big groups. For example, animals like thebelong to the group that eats other animals while animals like the sheep belong to the group that eats grass and leaves.Animals are to us. Men hunt wild animals for their fur and meat. Domestic animals are even more important to men. Without them, life will be . Cows and dogs are useful tofood. Skin(皮) of some animals can beexpensive coats and地球上重1千克的物体在月球上只有524千克重，那么在地球上重40千克的物体在月球上重______千克．