Slow down. Let me the document before closing the Windows. [ ] A．to save B．saves C．save 题目和参考答案——青夏教育精英家教网—

题目内容

Slow down. Let me ________ the document before closing the Windows.

[　　]

A．to save

B．saves

C．save

答案：C

练习册系列答案

课课练与单元测试系列答案

世纪金榜小博士单元期末一卷通系列答案

单元测试AB卷台海出版社系列答案

黄冈新思维培优考王单元加期末卷系列答案

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 islong, 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.
【小题1】 When the traffic lights turn ______, we will stop driving a car.
A. red    B green     C. yellow
【小题2】According to the passage, the scattering of the red light is the _______.
A. longest    b. weakest       C. farthest
【小题3】 The underlined word "wavelength" means________ in Chinese.
A.波浪        B.光波      C.波长
【小题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
【小题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

Traffic rules help to keep order on the road. They also help to keep people   26 . The pedestrian(行人) has as many rules to   27  as the driver of a car. You should walk on the sidewalk(人行道) or at the side of the road. Always look   28  before you walk across the street.
If you like riding a bike, don’t ride in the middle of the road or run   29  red traffic lights. When you ride a bike with a friend, don’t look around or talk.If you drive a car, you should   30  at the traffic lights. You must always   31  a seat belt(安全带). Without belts   32  the driver and the passengers may be badly hurt in a sudden accident.
You may not need to take a bus, but   33  if you have to travel in one. Get on or get off a bus only when it comes to a   34 . When it is full, don’t try to get inside   35  you may fall off.
Traffic rules are also called Road Safety rules. The maxim(格言) for all road users is “Thinking about others”.

As we all know, the ocean moves. But waves breaking on the beach make the ocean fun. When you stand on the shore and look at the waves, it seems like the water is moving towards you. But the water is not really moving forward. The moving you see is wave energy. And wave energy comes from the wind.

Let’s think about how this works. As wave energy passes through the water, the energy makes particles （粒子） of water move up and down. Just give you an example of a wave passing under a basketball. We put a basketball on the sea. When the wind blows, a wave comes from behind the basketball. The basketball moves up to the top with the wave. Then the wave continues and leaves the basketball behind. The basketball looks lower, but it doesn’t move forward. That’s because the wave energy just moves the water which is under the basketball.

　 So why can you see a wave knock you down on the shore？When a wave moves toward the shore, the bottom of the wave slows down because it meets the ocean floor. But the top, which is called crest(浪峰), keeps moving. The different action causes the wave to fall over or break onto the shore. If a wave is very large, it carries a lot of energy when it hits the land. As time goes by, waves can break up and carry away the rocks and other things on the shore. Shorelines are changing all the time because of wave action.

1.______ is really moving forward when you look at the wave.

A．Water B．The basketball C．Water and wave energy D．Wave energy

2.Match the sentences with the pictures and the right answer.

(1) The basketball moves up to the top with the wave.

(2) The basketball continues and leaves the basketball behind.

(3) When the wind blows, a wave comes from behind the basketball.

A．a—(2) b—(1) c—(3) B．a—(3) b—(1) c—(2)

C．a—(1) b—(3) c—(2) D．a—(3) b—(2) c—(1)

3.Which of the following is NOT true according to the passage?

A．Wave energy comes from the water.

B．Large waves carry plenty of energy.

C．Wave action makes shorelines change all the time.

D．The bottom of the wave is easy to slow down.

4.The underlined word “it” ( Paragraph 3) refers to “________”.

A．particles of water B．the shore C．the wind D．the bottom of the wave

5.The main idea of this passage is ______.

A．what makes particles of water move B．how a basketball moves on the ocean

C．how wave energy causes wave action D．why a wave can knock you down

根据短文内容及所给首字母提示写出所缺单词, 并将完整单词填在下面对应题号后的横线上。

Air is very important to everything that lives. But the air we breathe is g 1 dirty. People all over the world are looking for w 2 to make it clean again.

Have you e 3 watched the smoke from chimneys(烟囱) rising high in the air? Have you s 4 the smoke from cars and trucks on roads or the smoke from planes? The smoke is not g 5 to breathe. If we want to keep healthy and strong, we need to breathe c 6 air.

W 7 more and more factories everywhere and more and more cars, trucks and planes, it is getting harder and harder to do with the air p 8 .

Scientists have a 9 taken actions to stop or slow down some of the things that make the air dirty. They will not stop working u 10 we have clean air again.

1. 2. 3. 4. 5.

6. 7. 8. 9. 10.

试题分类