题目内容

【题目】He often thinks things before he makes a decision.

A. about B. of C. out D. over

【答案】D

【解析】句意:在他做决定之前。他经常认真思考。短语think about表示考虑;think of表示想起;think over仔细地想;由句意“在作决定前他经常认真思考”可知,应用think over。根据题意,故选D。

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【题目】

Would you be able to go through a whole day without using a light bulb? Most people probably wouldn’t. Today, almost every building uses light bulbs as their main light source. Although we use them daily without much thought, light bulbs were once a costly and the newest technology. A lot of people’s hard work led to the light bulb’s invention, which has impacted our lives greatly.

The first light bulbs were glass containers that release light when an electric current heated a part inside called a filament (灯丝). Electric light bulbs are also known as incandescent (白炽) light bulbs. These days, we use energy-saving bulbs that are better for the environment. Nick Holonyak, Jr., an American engineer, invented the first light-emitting diode light (LED) in 1962. An LED light bulb uses one-third the electricity as an incandescent light and lasts far longer.

In 1802, a British scientist named Humphry Davy created the first electric light. Then, in 1835, other British scientists created the first constant stream of electric light, although the light didn’t shine very long. In the following decades, scientists experimented with light bulb filaments made of different types of materials, hoping to create a longer stream of electric light. In 1860, Joseph Swan found a material that produced a good light, but it burned out quickly. By this time, none of the light bulbs created were ready to be sold to the public for everyday use. Then, in 1878, Thomas Edison made more progress. He spent a lot of time researching what previous scientists had done. He and his team spent years experimenting with light bulb filaments. They eventually created the first light bulb that could release constant electric light for 1,200 hours. Edison immediately patented (取得专利) his light bulb design so that light bulbs could be produced and sold.

Light bulbs were safer and more convenient to use than oil lamps and candles. Increased use of light bulbs resulted in people being able to have a longer work day, so the average work day increased. Light bulbs also led to changes in building designs. Architects created windowless buildings, and lights could be placed in elevators and other new places.

1From Paragraph 1, we can learn that light bulbs were _______ in the past.

A. commonB. expensiveC. hardD. great

2According to the passage, which one invented the first electric light bulbs?

A. Nick Holonyak.B. Humphry Davy.

C. Joseph Swan.D. Thomas Edison.

3According to the passage, what was the main problem in improving light bulbs?

A. There was not enough money and engineering support.

B. There were no materials that could be used to save power.

C. Scientists from different countries couldn’t work together.

D. It was hard to find a filament material that shone long.

4According to the passage, which of the following statements in TRUE?

A. Light bulbs were as convenient as candles and oil lamps.

B. Edison made it possible to sell light bulbs to the public.

C. LED can save more power and make people’s work time longer.

D. Light bulbs make people stay in windowless rooms on work days.

5Which of the following would be the best title of the passage?

A. The invention we depend on.

B. The great inventers.

C. The history of science and technology.

D. What changes building designs?

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