把横线上所缺的单词补充完整
1.It's a very big animal.It can't jump.It is heavy. It has two long teeth.It's an____.
2.It can run very fast. It usually has two red eyes and two long ears. It often eats grass.It is a ___.
3.It can climb trees. It likes eating fruits.It has a long tail.It's a___.
4.It can walk on the land.But it walks slowly.It also can swim in the water.And it has a long neck. It is a___.