问题补充：
Do you know why different animals or insects have their special colors? Colors are used mainly to protect themselves.
Why can’t some birds easily catch locusts（蝗虫）? It is because locusts change their colors together with the change of the colors of crops. When crops are green, locusts look green. But as autumn comes, locusts change to the same brown color as crops have. Some other insects with different colors from plants are easily found and eaten by others. So they have to hide themselves for lives in the day 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 can’t be easily seen by hunters. This is because they have the colors much like the trees.
Have you ever noticed an even more strange thing? A kind of fish in the sea can send out black liquid when it faces danger. While the liquid spreads over, its enemies can’t find it. And it quickly swims away. So it has lived up to now though it is not strong at all.
【小题1】 From the article we learn that locusts .A．are dangerous to their enemiesB．are easily found by birdsC．change their colors to protect themselvesD．are small animals【小题2】How can insects with different colors from plants keep out of danger?A．They have to move quietly.B．They hide themselves in the day and appear at night.C．They have the colors much like their enemies.D．They run away quickly.【小题3】 Bears and lions can keep safe because .A．they live in forestsB．they like brown and grey colorsC．they move quietlyD．they have the colors similar to the trees【小题4】What does the word “liquid” mean in the last paragraph?A．气体B．固体C．液体D．水蒸气【小题5】 Which is the best title for this passage?A．The Main Use of Colors for Animals and InsectsB．Colors of Different Animals and InsectsC．The Change of Colors for Animals and InsectsD．The Change of Different Animals and Plants
答案：
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解析：
1.C 根据It is because locusts change their colors together with the change of the colors of crops可以知道蝗虫通过改变颜色来让自己不被发现，从而保护自己，故选C。
2.B 根据So they have to hide themselves for lives in the day and appear only at night.可知他们白天把自己隐藏起来，只在晚上出现，故选B。
3.D 根据because they have the colors much like the trees可知熊和狮子的颜色像树的颜色，也就是说他们的颜色相似，选D。
4.C 本题是猜词题，要联系上下文来看。根据While the liquid spreads over, its enemies can’t find it可知能在水中扩散让敌人不找不到他们的的是一种液体，也就是我们说的乌贼，选C。
5. C 主旨大意题的考查，文章主要讲的是动物和昆虫的颜色的改变，通过改变颜色他们能有效地保护自己，故C最佳。A,B只是文章提到了一个方面，D的植物变色文章未讲到。
