英语阅读练习Do you know why different animals or pests(昆虫) have their special colors?Colors in them seem to be used mainly to protect themselves.Some birds like eating locusts(蝗虫),but birds cannot easily catch them.Why?It is because locusts change their colors together with the change of the colors of crops(庄稼).When crops are green,locusts look green.But as the harvest time comes,locusts change to the same brown color as crops have.Some other pests with dif

英语阅读练习
Do you know why different animals or pests(昆虫) have their special colors?Colors in them seem to be used mainly to protect themselves.
Some birds like eating locusts(蝗虫),but birds cannot easily catch them.Why?It is because locusts change their colors together with the change of the colors of crops(庄稼).When crops are green,locusts look green.But as the harvest time comes,locusts change to the same brown color as crops have.Some other pests with different colors from plants are easily found and eaten by others.So they have to hide themselves for lives and appear only at night.
If you study the animal life,you'll find the main use of coloring is to protect themselves.Bears,lions and other animals move quietly through forests.They cannot be easily seen by hunters(猎人).This is because they have the colors much like the trees.
Have you ever noticed an even stranger act?A kind of fish in the sea can send out a kind of very black liquid(液体)when it faces danger.While the liquid spreads over(散开),its enemies(敌人) cannot find it.And it immediately swims away.
1：Why do locusts change their colors?____________
2:How many animals who can't change protect themselves?_____________
3:A ccording to the passage ,what colour may locusts be in summer?_____________
4:What other ways can animals protect themselves?(you may use Chinese here)________