If we are driving a car or crossing a street,...

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 (波长) 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.

1.______ has the longest wavelength of all light we can see.

A. Red               B. Green           C. Yellow          D. Black

2.Red light travels farther on ______ days.

A. windy             B. sunny           C. rainy         D. cloudy

3.Red can make people act more quickly because ____________.

A. red can make people happier              B. the scattering of red is very short

C. the scattering of red is very long           D. red can make people more excited

4.The underlined word “prevent” means ______ in Chinese.

A.逃避               B. 防止            C. 处理         D. 检查

5.The passage mainly tells us ____________.

A. why accidents happen                     B. how the red light travels

C. why we use red traffic lights               D. how to stop in time at traffic lights

九年级英语阅读理解中等难度题查看答案及解析

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 (波长) 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.

1.______ has the longest wavelength of all light we can see.

A. Red　　　　 　　 　 B. Green

C. Yellow　　　　　　 D. Black

2.Red light travels farther on ______ days.

A. windy　　　　　　 B. sunny

C. rainy　　　　 　 D. cloudy

3.Red can make people act more quickly because ____________.

A. red can make people happier

B. the scattering of red is very short

C. the scattering of red is very long

D. red can make people more excited

4.The passage mainly tells us ____________.

A. why accidents happen

B. how the red light travels

C. why we use red traffic lights

D. how to stop in time at traffic lights

九年级英语阅读理解中等难度题查看答案及解析

When the traffic lights turn red, we will stop driving a car or crossing a street. Why is red used for traffic lights instead of other colors?

As we know, scattering (散射) happens when light goes through the air. For the same media(媒质), if the wavelength is long, the scattering will be short. If the wavelength is short, then the scattering will be long.

Of all lights 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 sec the lights. It helps drivers stow down or stop in lime. 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 lights help drivers stop in time and help prevent accidents.

1. When the traffic lights turn ______, we will stop driving a car.

A. red    B green     C. yellow

2.According to the passage, the scattering of the red light is the _______.

A. longest    b. weakest       C. farthest

3. The underlined word "wavelength" means________ in Chinese.

A.波浪        B.光波      C.波长

4. What can the red light help drivers do?

A. It can help drivers in farther areas see the lights.

b. It can help drivers slow down or stop in time.

C. A and b

5.Which of the following is the best title?

A. Why do accidents happen

b. How does the red light travel

C. Why do we use red traffic lights

九年级英语阅读理解中等难度题查看答案及解析

阅读下面的短文，根据短文内容，从短文后面的选项中选出恰当的选项补全短文，并将选项的编号依次填入题后横线上。

If we are driving a car，we will stop when the traffic lights turn red．1.　　

As we know，scattering(散射) happens when light goes through the air．For the same media(媒质)，if the wavelength(波长) is long，the scattering will be weak．2.　　

Of all light we can see red has the longest wavelength，so the scattering is the weakest．That means the red light travels far. 3.　　

Using the red light can help drivers in farther areas see the traffic lights．4.　　

If drivers don’t see the traffic lights until they are close，they may not be able to stop the car in time and an accident may happen．Red can also excite people．5. In a word，red lights can help drivers stop in time and help prevent (防止) accidents．

九年级英语补全对话中等难度题查看答案及解析

阅读短文，从每题所给的ABC三个选项中选出最佳答案回答问题或完成句子。

When the traffic lights turn red, we will stop driving a car or crossing a street. Why is red used for traffic lights instead of other colors?

As we know, scattering (散射) happens when light goes through the air. For the same media(媒质), if the wavelength is long, the scattering will be short. If the wavelength is short, then the scattering will be long.

Of all lights 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 sec the lights. It helps drivers stow down or stop in lime. 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 lights help drivers stop in time and help prevent accidents.

1.When the traffic lights turn ______, we will stop driving a car.

A. red 　　 B green 　　 C. yellow

2.According to the passage, the scattering of the red light is the _______.

A. longest 　　 b. weakest 　　　　 C. farthest

3.The underlined word "wavelength" means________ in Chinese.

A.波浪　　　　　 B.光波　　　　 C.波长

4.What can the red light help drivers do?

A. It can help drivers in farther areas see the lights.

b. It can help drivers slow down or stop in time.

C. A and b

5.Which of the following is the best title?

A. Why do accidents happen

b. How does the red light travel

C. Why do we use red traffic lights

九年级英语阅读理解中等难度题查看答案及解析

Look out！The cars are running ______ fast______ we can't cross the street now.

A. too；to　　 B. so；that　　 C. such；that　　 D. enough；to

九年级英语单选题困难题查看答案及解析

—Good news！Self－driving cars will come into use in one or two years.

—Really？We're expecting to see how they ________.

A. are making　　 B. are made　　 C. make　　 D. will make

九年级英语单选题中等难度题查看答案及解析

Cars are lots of fun, but they could also be dangerous. We have to be careful when we drive them or ride in them.

It's always a good idea to put on your seat belt when you're in a car. Why? Think about this example: You put an egg on a skateboard and give it a push. If the skateboard hits a stone, it will stop, but the egg won't. It will fly through the air, hit the ground and break.

Now, think what would happen if you tied the egg to the skateboard. When the skateboard hits a stone, the egg won't go flying; it will stay safely on the skateboard.

Volvo, a famous Swedish carmaker, was the first to use seat belts in 1849.

Air bags are also very important for car safety, because sometimes a seat belt isn't enough. If the car is going really fast and runs into something, seat belts could even hurt the people who wear them. Most new cars have air bags in front of and next to the seats. When a car hits something, its air bags will come out quickly in less than one second to keep the people inside safe.

1.The passage mainly tells us ________.

2.The writer gives the example of the egg to _.

3.Seat belts can make us safer because .

4.Air bags are important for cars because _.

5.Which of the following is TRUE according to this passage?

九年级英语阅读理解中等难度题查看答案及解析

Cars are lots of fun, but they could also be dangerous. We have to be careful when we drive them or ride in them.

It’s always a good idea to put on your seat belt (安全带) when you’re in a car. Why? Think about this example: You put an egg on a skateboard and give it a push. If the skateboard hits a stone, it will stop, but the egg won’t. It will fly through the air, hit the ground and break.

Now, think what would happen if you tied the egg to the skateboard. When the skateboard hits a stone, the egg won’t go flying; it will stay safely on the skateboard.

Volvo, a famous Swedish carmaker, was the first to use seat belts in 1849.

Air bags are also very important for car safety, because sometimes a seat belt isn’t enough. If the car is going really fast and runs into something, seat belts could even hurt the people who wear them. Most new cars have air bags in front of and next to the seats. When a car hits something, its air bags will come out quickly in less than one second to keep the people inside safe.

1.The passage mainly tells us ______.

A．two important ways to keep safe in cars

B．how air bags work to make cars safe

C．how seat belts work to make cars safe

D．why we must tie the egg to the skateboard

2. The writer gives the example of the egg to ______.

A．tell us that eggs are easy to break

B．show how to wear a seat belt

C．show why it’s important to wear a seat belt in a car

D．tell us what a skateboard is

3. Seat belts can make us safer because ______.

A．we are interested in them

B．they can stop us from hitting other cars

C．they can help us stay safely on the seats

D．they are made of strong materials

4. Air bags are important for cars because ______.

A．they are made of plastic

B．they can also help us to keep safe in a car

C．they can keep cars running slowly

D．they’re put in front of and next to the seats

5. Which of the following is TRUE according to this passage?

A．When a car hits something, its air bags will come out a few minutes later.

B．It won’t be dangerous if there are seat belts or air bags in a car.

C．Now most of new cars still have only one air bag.

D．Volvo was the first to use seat belts.

九年级英语阅读理解中等难度题查看答案及解析

Cars are lots of fun, but they could also be dangerous. We have to be careful when we drive them or ride in them.

It's always a good idea to put on your seat belt when you're in a car. Why? Think about this example: You put an egg on a skateboard and give it a push. If the skateboard hits a stone, it will stop, but the egg won't. It will fly through the air, hit the ground and break.

Now, think what would happen if you tied the egg to the skateboard. When the skateboard hits a stone, the egg won't go flying; it will stay safely on the skateboard.

Volvo, a famous Swedish carmaker, was the first to use seat belts in 1849.

Air bags are also very important for car safety, because sometimes a seat belt isn't enough. If the car is going really fast and runs into something, seat belts could even hurt the people who wear them. Most new cars have air bags in front of and next to the seats. When a car hits something, its air bags will come out quickly in less than one second to keep the people inside safe.

1.The passage mainly tells us ________.

A. two important ways to keep safe in cars   B. how air bags work to make cars safe

C. how seat belts work to make cars safe     D. why we must tie the egg to the skateboard

2.The writer gives the example of the egg to _.

A. tell us that eggs are easy to break

B. show how to wear a seat belt

C. show why it's important to wear a seat belt in a car

D. tell us what a skateboard is

3.Seat belts can make us safer because .

A. we are interested in them

B. they can stop us from hitting other cars

C. they can help us stay safely on the seats

D. they are made of strong materials

4.Air bags are important for cars because _.

A. they are made of plastic

B. they can also help us to keep safe in a car

C. they can keep cars running slowly

D. they are put in front of and next to the seats

5.Which of the following is TRUE according to this passage?

A. It won't be dangerous if there are seat belts or air bags in a car.

B. Now most of new cars still have only one air bag.

C. When a car hits something, its air bags will come out a few minutes later.

D. Volvo was the first to use seat belts.

九年级英语阅读理解中等难度题查看答案及解析