It is well known that _________ air and water...

It is well known that _________ air and water are harmful to people’s health.

A. pollute　　　　　　　　 B. polluting

C. to pollute　　　　　　 D. polluted

高二英语单项填空中等难度题查看答案及解析

In today's world, almost everyone knows that air pollution（污染）and water pollution are harmful to people's health. However, not all the persons know that noise is also a kind of pollution, and that is harmful to human health, too.

People who work and live under noisy conditions usually become deaf（聋）. Today, however, scientists believe that 10 percent of workers in Britain are being deafened by the noise where they work. Many of the workers who print newspapers and books, and who weave（织）cloth become deaf. Quite a few people living near airports also become deaf. Recently it was discovered that many teenagers（几十岁的人）in America could hear no better than 65-year-old persons, for these young people like to listen to pop music and most of pop music is a kind of noise. Besides, noise produced by jet planes or machines will make people's life difficult and unpleasant, or even make people ill or even drive them mad.

It is said that a continuous noise of over 85 decibels（分贝）can make people deaf. Now The governments in many countries have made laws to control noise and make it less than 85 decibels. In China, the government is trying to solve not only air and water pollution problems but also noise pollution problems.

1.The text is mainly about    ____________ .

2.10 percent of the workers in Britain are being deafened because  _________.

3.About noise produced by jet planes or machines, which is wrong?

4. According to the text, a continuous noise of   _____  decibels can make people deaf.

5.The government of China is trying to solve    _______________ .

高二英语阅读理解中等难度题查看答案及解析

It is well known to all that water, ______ enough, can change into ice quickly．

高二英语单项填空简单题查看答案及解析

It is well known to all that water, ______ enough, can change into ice quickly．

A．if cooling                                            B．though to be cooled

C．when cooled                                       D．when is cooled

高二英语单项填空中等难度题查看答案及解析

_____ is known to all that oil and water don’t mix up.

高二英语单项填空简单题查看答案及解析

____ is known to all, persistence is a kind of quality and that’s ____ it takes to do anything well.

A. As; which         B. It; which         C. It; what             D. As; what

高二英语单项填空中等难度题查看答案及解析

It is well known to car drivers that red means “stop”, green means “go” and yellow means “hurry up and make that damn light”. Why those colors, though? The answer lies in the fact that the earliest traffic signals were designed for trains, not cars. They were red and green, gas-powered, and more than a little dangerous in the event of a leak.

Red is an inherited (继承的) symbol from railroads, which symbolizes danger in many cultures. As red has a longer wavelength than any other color on the visible spectrum (光谱), it can be seen from a greater distance than other colors. Red has meant “stop” since long before cars existed, with train signals’ use of red dating back to the days when mechanical arms lifted and lowered to indicate whether the rail ahead was clear.

Green’s wavelength is next to (and shorter than) yellow’s on the visible spectrum, meaning it’s still easier to see than any color other than red and yellow. Back in the early days of railway lights, green meant “caution”, while the “all-clear” light was, well, clear or white. It is said that several disastrous collisions happened after an engineer mistook stars in the night for an all-clear. Thus, green became “go”, and for a long time, railways used only green and red to signal trains.

From the earliest days of motoring up until mid-1900s, not all stop signs were red-many were yellow, because at night it was all but impossible to see a red stop sign in a poorly lit area. In 1950 the yellow stop-sign craze began in Detroit, a city that five years later installed its first electric traffic signal, which happened to include the very first yellow traffic light.

But what of those mysterious yellow stop-signs? As materials and technologies evolved, the ability to produce highly reflective signs meant that red could resume its natural spot in the sign hierarchy (层次体系，等级体系), leaving the still-highly-visible yellow to the domain (领域) of “caution”. That’s why school zones and buses, crosswalks, and other important warnings are yellow today.

1.What’s the main reason for the color red’s long being used to mean “stop”?

A.It has the longest wavelength on the visible spectrum.

B.It represents danger in many cultures.

C.It can be seen even in the dark area.

D.People prefer red to other colors.

2.Which of the following may the author agree with?

A.The meaning of red is culture–specific.

B.Yellow functioned as stop signs in the 1900s.

C.Green’s wavelength is just second to that of red.

D.Green’s role in traffic lights has changed over time.

3.What does the passage mainly talk about?

A.The significance of road traffic signs.

B.The history of railroad transportation.

C.The symbolic meaning of different colors.

D.The origin and development of traffic lights.

高二英语阅读理解中等难度题查看答案及解析

It is well-known that ____ year 2006 saw many developments in ____ science and technology, with those in the field of space science being particularly notable.

A. /; /                                    B. the; /                                         C. the; the                           D. /; the

高二英语单项填空简单题查看答案及解析

1.One of his great __________(雄心) is to become a great poet.

2.It is well known that this film is a________ from the novel of the same title.

3.Out of s__________ for the homeless children, he gave them shelter for the night.

4.The woman has an __________(优雅的) manner, but she is extremely difflcult to work with.

5.He p_______ for breath and then continued climbing.

6.The college raises annual visits to China by groups of students in order to raise their _____________(意识) of the importance and benefits of learning Chinese.

7.The lost car of the Lees was found _________(遗弃) in the woods.

8.Our school encourages students to actively p__________ in the exchange program.

9.What he said was not __________(相关的) to our discussion at all.

10.In the move most of the furniture was left to neighbours or ___________(分发) among friends.

11.The library has an a________ supply of books, so don’t worry about not finding what you need.

12.Plastic parts can ____________(替代) for metal ones, but they don’t last long.

13.We have made an __________(调整) and given you a special discount.

14.Life is full of choices and ___________(矛盾), so always listen to your heart.

15.It was really annoying; I couldn’t get access to the website you _________(推荐).

高二英语单词拼写中等难度题查看答案及解析

Many experts agree that once these treasures are _______ to the air, great harm will be done to them. So they think it better not to unearth the treasures.

高二英语单项填空简单题查看答案及解析