问题 解答题

30度的角在5倍的放大镜下是150度,你认为这句话对吗?为什么?

答案

因为,放大镜只是放大角的两条边,而两边叉开的大小没有变化,

30°的角在放大镜下,只有边延长,而表示角叉开的大小是不变的,还是30°,

所以30度的角在5倍的放大镜下是150度,这句话是错误的.

阅读理解

阅读理解。

   Animals, including insects, don't have a "language" like ours. They do not 'talk' to each other in words

and sentences. But if we watch them, we can see that they do have their ways of communicating (交流)

with each other.

   Can you see the rabbit's tail? When rabbits see this white tail moving up and down, they run away. They

know that they are in danger. The rabbit has told them something without making a sound. It has given

them a signal.

    Many other animals use this kind of "language". When a cobra (眼镜蛇) is angry, it raises its head and

makes itself look powerful (有力的). This warns other animals. When a bee (蜜蜂) has found food, it goes

back to its home. It cannot 'tell' the other bees where the food is by speaking to them, but it does a little

dance. This tells the bees where the food is.

    Some animals "say" things by making sounds. A dog barks, for example, when a stranger comes near.

A cat purrs when it is pleased. Some birds make several different sounds, each with its own meaning.

Sometimes we human beings speak in the same way. We make sounds like "Oh" or "Ah" when we are

frightened or pleased or when we drop something on our toes.

1. Which one is TRUE according to the passage? [ ]

A. Animals have languages like human beings.

B. Bees communicate with each other by dancing.

C. Animals can use words.

D. Animals are brave.

2. A rabbit uses its tail to ______. [ ]

A. warn other rabbits when they are in danger

B. tell other rabbits where food is

C. make itself look powerful

D. help it to run fast

3. When a cobra is angry, it ______. [ ]

A. makes a loud noise

B. raises its head

C. moves up and down

D. does a little dance

4. Several different sounds can be made by a ______. [ ]

A. rabbit

B. bee

C. bird

D. fish

5. From the passage, we know that ______ use words and sentences to express ideas and thoughts. [ ]

A. all living things

B. all animals

C. some birds

D. human beings

填空题