题目内容
Scientists have been taking a closer look at the lighting in our homes, offices and vehicles, and they're seeing a possible way to improve health.
Engineer E. Fred Schubert is talking about a new era of "smart" light sources. "We are looking at lighting systems that provide more than lighting," he says.
He's talking about light-emitting diodes(二极管),or LEDs. Most people know them as being quite small, like the lights that form. numbers on digital clocks. But recent technological advances have made them much more powerful, able to illuminate swimming pools and serve as traffic signals, for example.
Meanwhile, the lighting in offices and schools could be improved to help people stay healthy and productive, by acting on their internal body clocks. The 24-hour internal body clock is best known for governing cycles of alertness and sleep, and for producing jet lag(飞行时差) when people travel across time zones. Lights cues, especially blue light, help keep the clock on its daily cycle. We're pretty much blue-sky detectors. Our clocks count on bright days and dark nights.
But that's not necessarily what modern life delivers. During the winter in the northeast of America, for example, a person can commute roundtrip in the dark and sit all day in electric light that's fine for vision, but may be too dim to stimulate the body clock. That's called biological darkness.
How that affects people has been hard to document in the general population, but studies suggest such possibilities as seasonal depression, fatigue, sleep disturbances and maybe even cancer, especially breast cancer. Some studies suggest reduced productivity on the job. To counter that, architects and lighting engineers might someday take body clocks into account when they design lighting schemes. They may be encouraged to take steps like providing plenty of natural Night through windows and skylights, and installing bright blue LEDs near computer screens to give a dose of clock-adjusting light.
In the following places, where can we not find the LEDs？
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Part A
Directions: Read the following three texts. Answer the questions on each text by choosing A, B, C or D. Mark your answers on ANSWER SHEET 1.
"Family" is of course an elastic word. But when British people say that their society is based on family life, they are thinking of "family" in its narrow, peculiarly European sense of mother, father and children living together alone in their own house as an economic and social unit. Thus, every British marriage indicates the beginning of a new and independent family--hence the tremendous importance of marriage in British life. For both the man and the woman, marriage means leaving one's parents and starting one's own life. The man's first duty will then be to his wife, and the wife's to her husband. He will be entirely responsible for her financial support, and she is for the running of the new home. Their children will be their common responsibility and theirs alone. Neither the wife's parents nor the husband's, nor their brothers or sisters, aunts or uncles, have any right to interfere with them--they are their own masters.
Readers of novels like Jane Austen's Pride and Prejudice will know that in former times marriage among wealthy families were arranged by the girl's parents, that is, it was the parents' duty to find a suitable husband for their daughter, preferably a rich one, and by skillful encouragement to lead him eventually to ask their permission to marry her. Until that time, the girl was protected and maintained in the parents' home, and the financial relief of getting rid of her could be seen in their giving the newly married pair a sum of money called a dowry. It is very different today. Most girls of today get a job when they leave school and become financially independent before their marriage. This has had two results. A girl chooses her own husband, and she gets no dowry.
What does the author mean by "Family is of course an elastic word"？
听力原文：M: Do you mind telling me about your work in the factory？
W: Certainly not. I'm a machine operator working in the assembly workshop.
M: Oh, are you？ Then you have a six -day week, don't you？
W: Yes. And we work eight hours a day, but this includes a one -hour break.
M: What about the huge machines used in your factory？ I know you make heavy machines yourselves. But I wonder if you also use machines imported from abroad.
W: Most of them are made in China, some even by our factory. Only a few were bought from other countries.
M: But I see the machines turned out here are quite modem and efficient.
W: Following the national policy of self - reliance and hard - working struggle, we've tried our best in the past few years to improve our equipment. However, there is still a lot more to do.
M: Now the question about yourself. ! hope you don't mind it. How much do you earn each month？
W: My monthly wage is 3,500 RMB, not including the extra pay of about 500 for extra work I put in.
M: That sounds reasonable indeed. I'm very interested in worker's welfare here. What other benefits do you workers get, I wonder？
W: Like other factories in China, our factory offers free medical service for workers.
How many hours does the woman work every day except the break？
【C2】______someday I'd marry and have six children, and at Christmas my house would【C3】______with energy and love.
I found the man【C4】______shared my dream, but we had not reckoned【C5】______the possibility of【C6】______Undaunted, we applied,【C7】______adoption, and then he arrived.
We called him Our Christmas Boy【C8】______he came to us during that season of joy. Then nature surprised us again. We【C9】______two biological children to the family—not as many as we had【C10】______for, but three made an entirely satisfactory【C11】______
As Our Christmas Boy grew, he made it clear that only he had the expertise to select and
【C12】______the Christmas tree. He rushed the season, starting his gift list in November. Her pressed us into singing carols, our froglike voices contrasting【C13】______his【C14】______gift of perfect pitch. Each holiday he【C15】______us up, leading us through a round of merry chaos.
Then, on his 26th Christmas, he left us in a car accident【C16】______his way home to his wife and infant daughter. But first he had stopped【C17】______the family home to decorate our tree.【C18】______stricken, his father and I sold our home, where memories【C19】______every room, and moved away. Seventeen years later, we grew old enough to return home, and【C20】______into a small quite house, like the house of my childhood. Our other son and daughter had married and had begun own Christmas traditions in another part of the country.
【C1】
W: Thank you for your advice. But my bike has got a flat tyre.
How would the woman probably get to work？
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