Turn off the light before you ． [ ] A． are leaving B． will leave C． leave D． have left 题目和参考答案——青夏教育精英家教网—

题目内容

Turn off the light before you ________．

[　　]

A．

are leaving

B．

will leave

C．

leave

D．

have left

答案：C
解析：

从句连词before引导时间状语从句。时间状语从句中，谓语动词用一般现在时态代替一般将来时态。

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Ⅳ．阅读理解（共15小题；每小题2分，满分30分）

阅读下列短文，从每题所给的四选项（A、B、C和D）中，选出最佳选项，并在答题卡上将该选项涂黑。

There’s been a lot of talk about white-and-blue collar workers, and you may have even heard of gold collar workers, but lately a new color of collar is making its way into China’s urban vernacular（土话）—green. Green collars say no when work is life and life is work. They choose to get out of the fast lane（车道）, and explore new ways of living “green”.

Living green doesn’t mean someone is working as an environmentalist, biologist or scientist. Instead it is more of a lifestyle choice. A typical green collar is well educated like a white-collar but physically tough like a blue-collar, likely born in the 70s or 80s of the last century and living in one of China’s big cities, with a monthly income well above 5,000 yuan （about US $700）.

The life of a green collar may go something like this; Turn off the mobile phone after work, eat only healthy food rich in vitamins, go on hikes every weekend, and like to help the underprivileged.

Green collars even have their own club. In Beijing, the Green Collar Club is for people who share a “be happy, healthy and helpful” spirit. The club often holds charity parties and uses the donations for environmental protection and poverty relief（摆脱贫困）projects in China.

“They are successful in their careers, but do not miss the pleasures in life. They have a lot of money, but do not fall slave to it.” said Zuo Shiguang, one of the founding members of the club.

1．What is the passage mainly about?

A．Differences between white-and-blue collars and green collars.

B．The increasing awareness of environmental protection.

C．New trends of life in China’s big cities.

D．The lifestyle of green collars.

2．Green collars are living green because_______.

A．they have a large income to use

B．they refuse to live an unhealthy life

C．they spend a lot of money and time in the open

D．they devote themselves to environmental protection

3．Green collars will_______after work.

A．prefer to be left alone

B．have fun with old friends

C．think nothing about work and more

D．do a lot of extra work at home

4．What ’s Zuo Shiguang’s attitude towards green collars?

A．Appreciative. B．Doubtful. C．Negative. D．Neutral.

5．The underlined part “the underprivileged” probably refers to those who are_______.

A．in heavy polluted areas B．in faraway places

C．in a poor state of education D．in unfavourable conditions

The biggest safety threat（威胁）facing airlines today may not be a man with a gun ,but the man with portable（便携式）computer in business class .In the past 15 years ,pilots have reported about over 100 incidents that could have been caused by electro-magnetic interference(电磁干扰) .The source of this interference remain unclear ,but increasingly ,experts are pointing the blame at portable electronic devices（设备）such as portable computers ,radio and mobile telephones .
RTCA ,an organization which advises the aviation industry ,has suggested that all airlines ban, such devices from being used during “key” stages of flight ,particularly take-off and landing .Some experts have gone further ,calling for a total ban during all flights .Nowadays ,rules on using these devices are left up to airlines. And although some airlines ban passengers from using such equipment during take-off and landing ,most are not willing to exercise a total ban ,if many passengers want to work during flights .
The difficulty is understanding how electromagnetic fields might affect an aircraft’s computers .Experts know that portable devices give off radiation which affects those wave lengths which aircraft uses for communication .But because they have not been able to reproduce these effects in a laboratory ,they have no way of knowing whether the interference might be dangerous or not .
The fact that aircraft may be in trouble because of the interference raises the danger
that some people may use radio systems in order to damage navigation（导航）equipment .As worrying ,though ,is the passenger who can’t hear the instruction to turn off his radio because the music is too loud .
【小题1】.
.What is said about over 100 aircraft incidents in the past 15 years ?
A They may have taken place during take-off and landing .
B They have been caused by the damage to the radio systems .
C They were said to have resulted from electro-magnetic interference .
D They were caused by the passengers’ portable computers .
【小题2】.
. Few airlines want to refuse a total ban on their passengers because ____ .
A they have other effective safety measures to fall back on
B they don’t believe there is such a danger as radio interference
C the effect of electromagnetic interference is yet to be proved
D most passengers refuse to take a plane which bans the use of radio
【小题3】.
. Why is it difficult to see the effects of electromagnetic fields on computers ?
A Experts lack proper equipment to such research .
B It is dangerous to carry out such research on an airplane .
C It remains a question what wave lengths are to be interfered with .
D Scientists are not able to produce the same effects in laboratory .
【小题4】.
It can be inferred from the passage that the author ___ .
A hasn’t formed his own opinion on this problem
B has fully understood the danger of electromagnetic interference
C regards it is as unreasonable to exercise a total ban during flight
D is in favor of banning passengers’ use of electronic devices

May I have you attention please? I have few things to tell you. When you have class here in the language lab, please be here a little early. Change your shoes before enter the lab. Don’t bring anything here except your text books. When you are into, please don’t touch these machine without permission. Always do as the teacher tell you to. In class you should only speak the English, not Chinese. Recorders can be used make a copy of the listening materials. When class over, turn off your machines and leave the lab one by one.

That’s all. Thank you.

Wildlife faces threats(威胁)from habitat destruction, pollution, and other human actions. Although protecting wildlife may seem too hard at times, even small actions in your own neighborhood can help protect many different animals. Here are some tips on how to protect wildlife through small actions.

1．Create wildlife friendly areas in your backyard.

When trying to make your garden more beautiful, you can choose plants that can provide food and shelter to native wildlife. This will also help cut down on pollution. And bird or bat houses to your yard or garden to attract and shelter these species.

2．Avoid harming the natural ecosystem(生态系统)in your area.

Some plants from other places can kill or harm native plants that provide food and shelter for wildlife.

3．Have a greener lifestyle.

By using less water and fewer fuels, you will be helping to protect the wildlife around you. Take buses or the subway when you can, turn off electric devices when you're not using them, take shorter showers, and keep your room temperature at or below 68 degrees during the winter.

4．Buy products that are wildlife friendly.

Don't buy products that are made from endangered animals. Keep in mind that some endangered animals are killed by traps, catches or hunters who are after other wildlife within the same habitat.

5．Donate money or time to organizations that protect wildlife and their habitats.

You can give money to organizations or groups that protect wildlife species in your neighborhood.

1. We infer that the purpose of this passage is to________.

A．tell us why protecting wildlife is extremely important now

B．suggest that we protect wildlife through actions

C．explain why protecting wildlife is not as hard as people think

D．give us some tips on how to protect wildlife through small actions

2. Which of the following threats to wildlife is NOT mentioned in the passage?

A．Animal diseases.

B．Loss of habitat.

C．Pollution.

D．Hunters.

3. In which section of a newspaper would you most probably read this passage?

A．Environment B．Teaching

C．Business D．Geography

The following are the results of the tests done by “Family and Home Magazine” on some Pocket Tape-Recorders on the market now.

Pearlcorder S702 $64

This simple model at the bottom of the Olympus range scored the most points for its excellent quality of recording. Background noise hardly affects the sound and recording from a pocket is perfectly possible, but it doesn’t turn off automatically.

Tape length: 30minutes per side. Weight: 240g.

Sony M9 $49.95

Small and very good looking, Sony’s latest offering scored most for its appearance. Sounds clear, but there is slight machine noise. The big control buttons are a great improvement on some of the complicated little controls on other tape-recorders. It doesn’t switch off automatically, but a red light shows if the machine is still running.

Tape length: 60minutes per side. Weight: 195g.

Sony M400 $115

Lots of little control buttons that make a noise are difficult to use. Recording is good but machine noise loses points. Tape counter and automatic switch-off when tape has finished recording or rewinding are useful.

Tape length: 60 minutes per side. Weight: 230g.

Imperial OEM MC7 $ 29.95

Cheap and simple compared with the rest, but recording is good as long as there is no background noise. Use only its own-make of cassette. No light to show it is on; no fast-forward button and the record button makes a loud noise.

Tape length: 30 minutes per side. Weight: 285g.

Philips 585 $80

Handsome and simple to use, but recording is very poor at more than the recommended distance of 5 cm-designed for dictation. No recording light.

Tape length: 15 minutes per side. Weight: 220g.

1.The machine that produces the best recording with the least unwanted noise is _____.

A．Pearlcorder S 702 B．Sony M9 C．Sony M400 D．Imperial OEM MC7

2.If you want a machine which turns off automatically and weighs very little you should choose _____.

A．Pearlcorder S 702 B．Sony M9 C．Sony M400 D．Philips 585

3.Which of the following allows you to record longest but costs you least?

A．Philips 585 B．Imperial OEM MC7 C．Sony M400 D．Sony M9

4.What disadvantage does only the Imperial OEM MC7 have?

A．No light shows when it is on. B．It requires a special cassette.

C．It picks up background noise . D．The record button makes a noise.

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