题目内容

 It took us ________ to finish the experiment on the monkey

  A) an hour or two                     B) one or two hour

C) one and a half hour’s time            D) one hour and a half time

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Windows not only let light in to cut down an electricity use for lighting, but the light coming through the window also provides heat. However, windows are not something people typically associate with being a cutting edge technology. Researchers are now working on new technologies that enable a window to quickly change from clear to dark and anywhere in between with a turn of a switch.

“It took us a long time to figure out what a window really is,” says Claes Granqvist, a professor of solid—state physics at Uppsala University in Sweden.“It’s contact with the outside world. You have to have visual contact with the surrounding world to feel well.” So, windows and natural light are important for improving the way people feel when they’re stuck indoors.

Yet, windows are the weak link in a building when it comes to energy and temperature control. In the winter, cold air leaks in. When it’s hot and sunny, sunlight streams in. All of this sunlight carries lots of heat and energy. And all of this extra heat forces people to turn on their air conditioners. Producing cold air, which can feel so refreshing, actually suck up enormous amounts of electricity in buildings around the world.

Windows have been a major focus of energy research for a long time. Over the years, scientists have come up with a variety of strategies for coating, glazing, and layering windows to make them more energy efficient. Smart windows go a step further. They use some technologies involving changes of color.

Electrochromic windows use electricity to change color. For example, a sheet of glass coated with thin layers(层) of tungsten oxide(氧化钨) works a bit like a battery. Tungsten oxide is clear when an electric charge is applied and dark when the charge is removed, that is, when the amount of voltage(电压) is decreased, the window darkens until it’s completely dark after all electricity is taken away. So applying a voltage determines whether the window looks clear or dark.

One important feature that makes a smart window so smart is that it has a sort of “memory”. All it takes is a small shock of voltage to turn the window from one state to the other. Then, it stays that way. Transitions take from 10 seconds to a few minutes, depending on the size of the window. The development of smart windows could mean that massive air conditioning systems may no longer need.“In the future,” Granqvist says,“our buildings may look different.”

67.Which statement does not indicate the importance of windows as described in the first two paragraphs?

A.Windows can change from clear to dark to save energy.

B.Windows help to save energy by letting light in.

C.Windows help to save energy by providing heat.

D.Windows enable people to have contact with the outside world.

68.According to the passage, smart windows are windows_______.

A.that are coated                        B.that use electricity

C.the color of which can be changed        D.that have many layers

69.To make electrochromic windows change color, what is applied to the window glass?

A.Electricity.     B.Tungsten oxide.    C.A battery.         D.A voltage.

70.What will be the benefit if the research on smart windows turns out to be successful?

A.The buildings will look different.

B.Windows can be as large as you want.

C.We may not need air conditioners any more.

D.They are less expensive than traditional windows.

 

One day in January, my uncle, my cousin and I decided to go hunting.We left by car in the afternoon.It was a Range Rover with four-wheel drive.It took us three hours to get there.After we arrived at 5:15 p.m., we fixed the tent, then made coffee and had a short rest.After that, we went hunting, using a falcon(猎鹰).We spent two hours without finding anything.On our way back to the camp, my cousin saw a rabbit.I removed the falcon’s bead cover and let go of the aggressive falcon.When the rabbit saw the falcon, it ran fast, but my falcon was a professional hunter.He flew up and came down to trick the rabbit.After two minutes, the rabbit was caught.We took it back to the camp to cook our dinner.We ate the delicious food, drank Arabic coffee, and sat around the fire talking until 10:30 p.m.

We left the camp the next day at 7 o’clock in the morning.We went north.However, around 10:00 a.m.our car got stuck in the sand! We spent about three hours trying to pull out the car without any progress.Finally, we decided to walk.As it was hard for an old man or a young boy to walk more than 40km in the desert, I decided to get help myself.I took a bottle of water with me and started to walk south alone.I knew the way well, but it was a long way in the sand.I walked more than four hours without stopping.When I felt so tired and thirsty, I stopped to rest.I drank all the water and slept for around two hours.

When I got up, it was dark.I continued to walk south.I was worried about my uncle and cousin.Suddenly, I met a Bedouin man who was riding his camel.He took me to his house.When I had had enough rest, I asked him to take me to the road where I found a car.It took me to the city to get help.I had one day to get back to my uncle and cousin.When I got back to them, they were so happy because I had gotten help and they were able to see me again.

1.Which word can best describe the first evening of their hunting trip?

       A.Adventurous.     B.Enjoyable. 

       C.Stressful.            D.Exhausting.

2.How did the writer finally get out of the desert?

       A.He was picked up by a car.

       B.A camel took him to the road.

       C.A passer-by Bedouin helped him.

       D.His uncle and cousin found and rescued him.

3.What can be inferred from the story?

       A.It’s an easy job to walk 40km in the desert.

       B.The author loved to go hunting with his family.

       C.The hunting trip is much longer than expected.

       D.To hunt in the desert one must train a falcon well.

 

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