Many people think that hippos（河马） are cute and funny-looking． They are really fat and they have short， thick legs． They also have little round ears that wiggle（摆动） sometimes．
Hippos look funny， but you shouldn't judge a book by its cover． Hippos are extremely violent and dangerous． In fact， they kill more people than any other animal in Africa． Think of how many dangerous animals that Africa has． It has got crocodiles， snakes， lions， elephants， and many more． Hippos also are more dangerous than all of them．
Hippos are naturally very dangerous animals， but there are some situations that make them even more dangerous than normal． They are very territorial． That means that they stay in one area which they consider to be their private area． If a person or animal enters a hippo's area， the hippo will attack． Hippos often attack when they are returning to the water． Hippos eat on land and return to the water at dusk． If a hippo sees an animal when it's returning to the water， it will become violent．
Hippos are so strong that they often kill crocodiles． There are two reasons that explain why hippos and crocodiles often fight． First of all， hippos and crocodiles live in the same areas． Since hippos are territorial， they don't like having crocodiles nearby． Also， crocodiles often eat young hippos． For that reason， adult hippos frequently kill crocodiles．
Mother and daughter hippos have close relationships． However， hippos don't have any other close relationship with each other． Hippos often live together in large groups， but scientists don't know why． It's hard to study the behavior of male and female hippos， because males and females look the same．
Hippos are violent， but they are herbivores． A herbivore is an animal that eats only plants． An adult hippo eats about 50 kilograms of plants every day． Hippos are much more comfortable in the water， but they can run fast on land． Their top speed is about 19kilometers per hour． That's much faster than humans can run．



What is the text mainly about？ ______

A. The fight between hippos and crocodiles．
B. How to tell male hippos from female ones．
C. Africa's most dangerous animal--- hippos．
D. Why hippos get violent．

If an animal is territorial， what does that mean？ ______

A. It is afraid of other animals．
B. It stays within a limited area．
C. It does not like to live in large groups．
D. It does not want other animals to enter its area．

What is the author's purpose in writing the text？ ______

A. To inform．
B. To entertain．
C. To instruct．
D. To persuade．