2．Many animals need to move across large distances.Often they do this as part of their natural migration（遷徙）.Sometimes animals need to move to a new area when food gets low or conditions get worse.However，humans have taken over huge areas of the planet.Roads and highways cut up the remaining natural areas into many small sections，making it dangerous for animals to move.
Many people are working to help animals by creating "wildlife corridors（走廊）"，trying to reconnect smaller natural areas so that animals can move over larger areas.One important step in creating these corridors is building wildlife bridges and tunnels to give animals a way to safely cross dangerous roads.These changes don't just help animals，but they also save human lives by avoiding accidents.
On China's Hainan Island，scientists created a bridge for gibbons，an animal that lives in southern Asia.But in 2014，natural accidents caused huge gaps in the forest，forcing them to make dangerous jumps.Scientists created a simple and cheap bridge，which solved the problem.In 2018，the experts in Utah，America built a wildlife bridge over the busy highway.A 4.8-kilometer fence was created to help guide animals to the bridge.Normally，animals take a long time to discover and begin using wildlife bridges，so experts didn't expect the bridge to get much traffic for several years.However，to their surprise，many different kinds of animals have already used the bridge.
Now people in other countries are looking to try similar ideas.In Brazil，scientists want to create bridges to help animals cross the hundreds of miles of highway that cuts through the Amazon rainforest.In Uttarakhand，India，an eco-bridge made from all-natural materials has been built.Though it's high in the trees，it's expected to help smaller animals on the ground by reminding drivers that they're in an important natural area with lots of wildlife.Already，the bridge has got a lot of attention，with many people taking selfies（自拍照）in front of it.
（1）Why are the wildlife corridors created？
A．To avoid the attack from animals.
B．To offer a way to protect animals.
C．To improve animals' living conditions.
D．To bring more convenience to humans.
（2）How does the bridge in Utah surprise the experts？
A．Animals need no guide to it.
B．Animals take more time to cross it.
C．It has made the traffic dangerous.
D．It is used by many animals sooner.
（3）What do we know about the eco-bridge in India？
A．It has become a hit for tourists.
B．It is made of man-made materials.
C．It acts as a reminder for the hunter.
D．It serves as a sign of a natural area.
（4）How is the text mainly developed？
A．By making a comparison.
B．By listing some examples.
C．By showing causes and effects.
D．By following the order of time.
