题目内容
What do you hear? Sounds all around you! You can hear the sound of traffic, the wind in the trees, a dog barking, your own breathing and lots of other things.
But what is sound? Sound happens when something vibrates(振动)or shakes. We can make something vibrate by hitting it. Try this experiment. Put your ruler on your desk so that part of it sticks out(伸出)over the edge . Put your hand on the part of the ruler that is on the desk. Now pull the part that is sticking out over the edge down, and then let it go. The part you let go will vibrate. It will move up and down very quickly, and give out sound.
The part of the ruler sticking out over the edge of the desk produced the sound. If you make that part longer, you will hear a lower sound. When you shorten it, you will hear a higher sound. Why does this happen?
When you shorten the ruler, it will vibrate more quickly. When something vibrates more quickly it produces a higher sound. If you lengthen the ruler, it will vibrate more slowly. When something vibrates more slowly, it produces a lower sound.
61. How does sound happen?
A. When something vibrates. B. When something shakes.
C. When a ruler is put at the edge of the desk. D. A and B.
62. We can hear a sound if we make the part of the ruler sticking out over the edge of the desk longer.
A. higher B. lower C. strong D. nice
63. The word “lengthen” in the passage means“ ”.
A. 加长 B. 缩短 C. 敲击 D. 摇动
64．The best title of the passage is“ ”.
A. An Experiment B.
C. Sounds Are Around Us D. Sounds
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The early 1900s were very different from today, when toys were still the delight of children everywhere.
Theodore Roosevelt's Presidency marks the beginning of the “Teddy Bear”. In the year 1902，toy bears were named “Teddy” after the president's nickname. The Teddy Bear became known worldwide and it was only a few years later that the Teddy Bears were mass produced.
In 1913，an item called the Erector Set was invented. It was a steel，motorized toy that children could use to build models of anything. Its creator was A．C.Gilbert，a medical doctor.
Charles Pajeau created a similar wooden set called Tinker Toys in the year 1914.Tinker Toys were made for younger children.
Raggedy Ann dolls first came on the scene after newspaper cartoonist Johnny Gruelle reproduced the doll he made for his daughter. That was in 1915.
The following year，an architect's son named John Lloyd Wright，invented Lincoln Logs，which were interlocked to make structures.
Two years after Mickey Mouse was created，stuffed(填塞)Mickey Mouse dolls were made by Charlotte Clark. This was the start of Disney merchandise.
The yoyo became popular in the United States after Donald Duncan bought a yoyo company in 1929.
The ViewMaster，a three dimensional viewer，was developed by a camera enthusiast named William Gruber. The toy became popular when Gruber licensed Disney characters to make still, 3D images from Disney movies and television programs.
Finally，in 1940，model airplanes were mass produced. They started out as a way for manufacturers to sell planes to the military，but later caught on as a toy.
The toys that we know and love today have had their roots from these ancient times. Thanks to all these creative man’s efforts, we know otherwise what we may never know.
【小题1】Why were toy bears named “Teddy”？
| A．To be suitable for mass production |
| B．To be easily pronounced by children. |
| C．To meet the advertisers' needs. |
| D．To memorize President Theodore Roosevelt |
| A．Shape | B．Material used | C．Themes | D．Price |
| A．After William Gruber was born |
| B．After Gruber licensed Disney characters |
| C．Two years after Mickey Mouse was created. |
| D．When Disney merchandise was started |