8．In nature，you may see many insects （昆蟲）and animals of different colors．Have you ever wondered why？
Locusts（蝗蟲） are super delicious food for birds，but it is not always an easy job for birds to catch them．It is neither because locusts are good jumpers or runners nor because they are smarter than their enemies．The reason is that the colors of locusts change with the colors of crops（莊稼）．When crops are young，locusts look green．But when autumn comes，locusts change to the yellow and brown color as crops do．Brown bears，tigers and other animals move quietly through forests．They can't be seen easily by their enemies．This is because they have colors similar to the trees．For the same reason，polar bears that live on a land of snow and ice are white．Butterflies and bees living among the flowers are colorful like flowers．Soil insects are mostly dark-colored and they live under the soil in a dark and wet environment．However，insects with colors different from plants can easily be found and eaten by others．So in order to survive，they have to hide themselves in the daytime and appear only at night．
Have you ever noticed some even stranger acts（行為）？The ink fish in the sea can send out some very black ink when it faces danger．As the ink spreads over，its enemies will find themselves suddenly in a dark world．At the same time the ink fish immediately swims away．That is how it keeps itself safe though it is not strong at all．
46．It is not easy for birds to catch locusts becauseD．
A．locusts are good runners
B．locusts can jump very high
C．locusts are smarter than birds
D．locusts can change their color
47．According to the passage，most soil insectsA
A．do not have bright colors
B．change their colors with the soil
C．do not live in a dark and wet environment
D．eat colorful insects like butterflies and bees
48．What's the meaning of the underlined word"survive"in the passage？D
A．繁殖 B．產(chǎn)卵 C．覓食 D．生存
49．The ink fishBso that its enemies will not see it．
A．changes its color
B．makes the water around it black
C．a(chǎn)ppears only at night
D．hides itself in the sea rocks
50．What is the main idea of this passage？C
A．Some insects and animals have different skills．
B．Some insects and animals are clever than we think．
C．Some insects and animals use colors to protect themselves．
D．Some insects and animals can get used to the environment easily．
分析 文章大意：這是一篇科普知識類遇到，短文主要介紹自然界有許多昆蟲和動物都有不同的顏色．本文以蝗蟲、棕熊、老虎、北極熊、蝴蝶和土壤昆蟲為例敘述了動物的保護色，并且介紹了墨魚保護自己的方式．
解答 46．答案：D．細節(jié)理解題．根據(jù)第二段第二行The reason is that the colors of locusts change with the colors of crops（莊稼）．原因是蝗蟲的顏色隨著農(nóng)作物的顏色而變化．可知，鳥不容易抓到蝗蟲是因為蝗蟲可以改變它們的顏色．選D．
47．答案：A．細節(jié)理解題．根據(jù)第二段第五行Soil insects are mostly dark-colored and they live under the soil in a dark and wet environment．土壤昆蟲大多是深色的，在黑暗潮濕的環(huán)境下生活在土壤下．可知，大多數(shù)土壤昆蟲沒有明亮的顏色．選A．
48．答案：D．詞意猜測題．根據(jù)上句However，insects with colors different from plants can easily be found and eaten by others．然而，與植物不同顏色的昆蟲很容易被其他人發(fā)現(xiàn)并吃掉．可知，所以為了"生存"，不得不隱藏自己．選D．
49．答案：B．細節(jié)理解題．根據(jù)最后一段The ink fish in the sea can send out some very black ink when it faces danger．As the ink spreads over，its enemies will find themselves suddenly in a dark world．海里的墨魚在面臨危險時能發(fā)出一些極黑的墨水．隨著墨水的擴散，它的敵人會突然發(fā)現(xiàn)自己在黑暗的世界里．可知，墨魚使周圍的水變黑以便它的敵人不會看到它．選B．
50．答案：C．主旨大意題．根據(jù)最后一段The ink fish in the sea can send out some very black ink when it faces danger．海里的墨魚在面臨危險時能發(fā)出一些極黑的墨水．That is how it keeps itself safe though it is not strong at all．這是它如何保持自己的安全，雖然它不強．及蝗蟲、棕熊、老虎、北極熊、蝴蝶和土壤昆蟲，它們利用顏色保護自己的例子可知，短文主要講一些昆蟲和動物用顏色來保護自己．選C．
點評 閱讀題型，要注重句子與句子之間、段落與段落之間邏輯關(guān)系以及對篇章的整體理解．根據(jù)所給問題選擇正確選項完成試題．
