21、The roadrunner lives in the desert of the southwestern United States and northern Mexico．It is a bird，but it can only fly about as much as a chicken can．People gave it its name because they usually see it running across a road，but，of course，it spends more time among the plants of the desert than it does on roads．

The roadrunner is quite a large，bird--about 45 cm long and 25 high．People laugh when it runs because it looks so funny．It takes long steps and can run 30 kilometers an hour．

It eats many different kinds ~f food．Although it eats plants once in a while，it is mostly a meat eater．Most of its diet is insects，but it also catches birds，mice and other small animals．It is so brave that it even dare catch snakes and black spiders．

In the spring，a male roadrunner begins looking for a female as a mate．When he finds one，he gives her presents--a snake to eat or a branch to use in building a nest．Then they build their nest，the female lays eggs，and they raise their young．

In cold winter the roadrunner has an unusual way of keeping warm．In the early morning，the roadrunner stands with its back to the sun．It holds out its wings and lifts the feathers on its upper back．There is a small dark round area on the skin tinder these feathers and it collects heat from the sun and warms its body．Unlike most birds，it doesn't need to use a lot of energy to keep warm．

Some people in Mexican villages use roadrunner meat as medicine．They believe that because roadrunners can eat poisonous animals and not die，their meat should be good for human sickness．

               

1．The roadrunner gets its name because ________．

A．it is too large for a bird

B．it runs in the desert looking for snakes

C．it can hardly fly，yet it can run fast

D．it spends more time on roads than in the desert

2．When a male roadrunner looks for a female，it usually gives her ________．

A．wings               B．nests                      C．feathers          D．gifts

3．Some people in Mexican villages ________．

A．kill roadrunners to use their meat for sickness

B．learn to keep warm the way roadrunners do

C．stay away from poisonous roadrunners

D．become very friendly with roadrunners

4．From the passage we know that ________．

A．roadrunners eat all kinds of food，mostly plants

B．roadrunners fit into the environment very well

C．roadrunners live in the desert all over the world

D．roadrunners use a lot of energy keeping warm in winter