If we are driving a car or crossing a street, we will stop when the traffic lights turn red. Why do we use red rather than other colors?
As we know, scattering (散射) happens when light goes through the air. For the same media, if the wavelength (波長(zhǎng)) is long, the scattering will be short. If the wavelength is short, then the scattering will be long.
Of all light we can see red has the longest wavelength, so the scattering is the weakest. That means the red light travels far. In fact, it travels farther on rainy days.
Using the red light can help drivers in farther areas see the lights. It helps drivers slow down or stop in time. If drivers don’t see the red light until they are close, they may not be able to stop the car in time. An accident may happen. Red can also excite people. We can act more quickly when we see the color red.
In a word, red light helps drivers stop in time and help prevent accidents.
小題1:______ has the longest wavelength of all light we can see.
A.RedB.GreenC.YellowD.Black
小題2:Red light travels farther on ______ days.
A.windyB.sunnyC.rainyD.cloudy
小題3:Red can make people act more quickly because ____________.
A.red can make people happierB.the scattering of red is very short
C.the scattering of red is very longD.red can make people more excited
小題4:The underlined word “prevent” means ______ in Chinese.
A.逃避B.防止C.處理D.檢查
小題5:The passage mainly tells us ____________.
A.why accidents happenB.how the red light travels
C.why we use red traffic lightsD.how to stop in time at traffic lights

小題1:A
小題1:C
小題1:D
小題1:B
小題1:C

小題1:根據(jù)we can see red has the longest wavelength,描述可知選A。
小題1:根據(jù)In fact, it travels farther on rainy days. 可知選C。
小題1:根據(jù)Red can also excite people. We can act more quickly when we see the color red. 可知選D。
小題1:根據(jù)上文stop in time 及時(shí)停止,可知下文句意為預(yù)防阻止事故,故選B。
小題1:通過(guò)短文描述可知本文主要是介紹了人們?yōu)槭裁词褂眉t色作為交通信號(hào)燈,故選C。
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科目:初中英語(yǔ) 來(lái)源:不詳 題型:閱讀理解


Canberra is the capital of Australia. It is a modern and lively city with a population of over 345 000.
 
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科目:初中英語(yǔ) 來(lái)源:不詳 題型:閱讀理解


Top help you decide what might make a good pet ,we’ve put together a pet checklist .We’ve named some of the animals that are often kept as pets .We’ve shown some good points and bad points about each .And we hope it may help you make the best choice(選擇)
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科目:初中英語(yǔ) 來(lái)源:不詳 題型:閱讀理解

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科目:初中英語(yǔ) 來(lái)源:不詳 題型:閱讀理解

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科目:初中英語(yǔ) 來(lái)源:不詳 題型:閱讀理解

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4-6 ginger slices (姜片)
1 bunch of spring onions, cut into pierces
1 red tomato, cut into 8 pierces ,oil. salt and pepper
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l. Remove the bones from the fish.
2 Pour oil into a pan. Fly the ginger slices, and the spring onions Add the fish hones and oil.
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B.oil—fish bones—ginger slices and spring onions—apples, fish and tomato
C.oil—ginger slices and spring onions—fish bones—apples, fish and tomato
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科目:初中英語(yǔ) 來(lái)源:不詳 題型:閱讀理解

閱讀短文,根據(jù)內(nèi)容判斷正誤。正確的選“A”,錯(cuò)誤的選“B”
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20070212

 
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科目:初中英語(yǔ) 來(lái)源:不詳 題型:閱讀理解

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