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 　　　　　　　　　.

Do you have any foreign friends? Do you know their characteristics(特征)?
The Germans are very quiet and they always keep calm. They don’t like to speak more words. They look very serious. They like different kinds of amusements. The Germans are very hard—working. They like tidiness, especially the women, who always keep their home clean.
In some ways, the Englishmen look the same as the Germans. They are very quiet and never talk too much with the strangers. They are really polite, so we often hear they say “Thank you.” Or “Sorry.” The gentlemen are also the Englishmen.
The French’s holidays are very long. They like traveling and usually spend their long time staying in other countries. The Frenchmen are more outgoing than the Germans. It is very easy to make friends with them.
Compared to the Frenchmen, the Americans are more outgoing. And they are even opener than all of the Europeans. They don’t like to depend on others. So it is very common that the students do part-time jobs in their free time. And in Americans’ eyes, success is an important part in their life.
【小题1】According to the passage, ______are very quiet.