Light pollution threatens to prevent those wonderful sights _________being seen.A、fro

s the same()heavy()light oil is spilled into the water.

A.both/and

B.whether/or

C.neither/nor

D.because/so

dle, and light bulb, gradually drawing back the curtain of darkness. But a brighter world has its drawbacks.

An estimated 30 percent of outdoor lighting—plus even some indoor lighting—is wasted. Inefficient lighting costs U. S. about ＄10. 4 billion a year, according to Bob Gent of the International Dark-Sky Association, a nonprofit that aims to control light pollution.

Last year in Sydney, an estimated 2. 2 million Australians switched off their lights during “Earth Hour”, briefly reducing that city’s energy use by more than 10 percent. Motivated by such trends, more than two dozen cities worldwide went dim on March 29 this year in an hour-long demonstration.

A number of groups are trying to measure light pollution and assess its effects on the environment in the hope that people will reduce their own contribution to the problem. Scientists are trying to report how many stars we can see. In dark rural areas, about 2, 000 stars are typically visible at night, compared with“maybe five”in a bright city square—and about 5, 000 in centuries past.

People who are working while others are star-gazing may face the greatest risks. Nighttime exposure to white light can cause the growth of tumors (肿瘤) , experiments show. Two decades of research indicate that women who work night shifts have unusually high rates of breast cancer.

The word“drawbacks”in the first paragraph probably means_______.

A．benefits

B．interests

C．effects

D．problems

A. rushed

B. thrust

C. went

D. threw

A.on

B.two.

C.thre

D.as many as possibl

A. four-hour,three-fourths

B. four-hours,three-fourth

C. four-hours,three-fourths

D. four-hours,three-fourthes

Communication networks can be classified in terms of their physical arrangement or(73)Three common(73)are the star, bus, and ring.

A．structures

B．topologies

C．protocols

D．frames

A、RLS中断

B、RDA中断

C、CTI中断

D、THRE中断

Communication networks can be classified in terms of their physical arrangement or(74)Three common(74)are the star, bus, and ting.

A．structures

B．topologies

C．protocols

D．frames

t the benefits of drinking Chinese tea for such things as losing weight and staying alert, but the following points may be something new to you.

Chrysanthemum (菊花) tea, made of white chrysanthemums, is a must for office workers in the closed environment with radiation contamination.The white chrysanthemum is regarded as an ideal herb in Traditional Chinese Medicines (TCMs), which can clear away the heat and poisonous substance accumulated in the body.According to TCMs, the herb can aid in the prevention of sore throat and promoting the reducing fever and cooling you down.It is also well known for making people more alert and is often used to waken them.Ancient Chinese adopted the tradition of drinking chrysanthemum wine in autumn, believing the wine would keep healthy.

Since it’s impossible to drink wine in the office, TCMs doctors highly recommend the chrysanthemum tea, instead, especially for those who suffer from serious radiation pollution or experience dry mouth.However, doctors suggest that weak people (who are very sensitive to cold and always have cold hands and feet) should take less chrysanthemum tea, which will make them feel colder.

Mugwort (艾蒿) tea is another popular tea in China.If you drink a lot of water before sleep, you’ll find yourself looking tired and pale the next morning, and you may feel as bad as you look.Mugwort tea will help you eliminate tiredness and recover your high spirits.Only several grams of mugwort are needed for a cup of tea.The tea may also be effective for weight loss.

Unlike other teas, the fruit tea is very flavorful with a light sweet taste.The small red berry is not a common fruit, but a kind of traditional Chinese medicine that helps maintain good eyesight and get rid of the waste in bodies.Watching the lovely cherries swelling up in the glass is an enjoyable process, and adding several white chrysanthemum in the tea can make the tea more tasty and beautiful.

46.Why is chrysanthemum tea necessary for the office workers in the closed environment？()

A.It can help reduce radiation pollution

B.It can provide the weak with warmth and energy

C.It may be effective for weight loss

D.It may be a treatment to cold in autumn

47.What is the medicinal use of the white chrysanthemum？()

A.It makes people stay in shape

B.It keeps people in high spirits

C.It helps reduce a fever

D.It prevents a bad cold

48.According to the passage, the negative effect of chrysanthemum tea is ________.

A.making people look pale and tired

B.getting people addicted to the tea

C.having people experience dry mouth

D.letting the weak people feel colder

49.The function of red berries in the fruit tea is ________.

A.a decoration swelling up in the glass

B.a medicine helping maintain good eyesight

C.a fruit strengthening the immunity to colds

D.a flavor making the tea more tasty

50.What’s the passage mainly about？()

A.The medicinal use of chrysanthemum tea

B.The fruit tea is flavorful with a light sweet taste

C.The drinks we take in the break time

D.The healthy benefits of Chinese tea

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