There are two kinds of elephants on land. One is the Asian elephant and the other is the African(非洲的) elephant. A 15-year-old African elephant is about 4 metres and 8 tons. They are the biggest animals on land. So they are bigger than Asian elephants. How tall and how heavy is a baby elephant? It's about 100 cm and 100 kg. Elephants like to live together. We can often see them eat and drink together. We know dogs are very clever. But elephants are more clever than dogs. They can do many things for us. They can even(甚至) look after human babies. Elephants are really our friends.