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The ocean can be a great place to swim and play, it may also be useful in another way. Some scientists think that waves could help make electricity.
“Have you ever been on a surfboard or boat and felt yourself being lifted up by a wave?” asked Jamie Taylor of the Wave Energy Group in Scotland. “There is certainly a lot of energy in waves.”
Scientists are working on using that energy to make electricity. The United States and a few other countries have started doing research on wave energy, and it is already being used in Scotland.
Most waves are created when winds blow across the ocean. “The winds start out by making little ripples (波紋) in the water, but if they keep on blowing, those ripples get bigger and bigger and turn into waves,” Taylor said. “Waves are one of nature’s ways of picking up energy and then sending it off on a journey.”
When waves come towards the coast, people can set up dams(大壩) to block the water and send it through a large wheel called a turbine(渦輪). The turbine can then power an electrical generator(發電機).
We will never run out of wave power. Besides, wave energy does not create the same pollution as oil and coal do.
Oceans cover three quarters of the earth’s surface. That would make wave power seem perfect for creating energy around the world. But there are some disadvantages that need us to pay more attention to.
Jamie Taylor said that wave power still cost too much money. He said that its influence on animals in the sea is still unknown. Besides, wave power would get in the way of fishing and boat traffic.
With more research, “Many of these problems might be solved,” Taylor said. “Finding more energy sources(資源) is very important, for traditional sources of energy like oil and gas may run out some day.”
In the future, when you turn on a light button, an ocean wave could be providing the electricity!

【小題1】We can learn from the passage that__________________.

　　People know that some animals, particularly birds, can be trained to carry messages for them. From 3,000

B．C to now, pigeons have been used as “postmen” either in war or in peace.

　　In 1870, when the Germans surrounded Paris, the city was cut off from all the usual means of communication. The people tried many different ways of sending news. One way was to use pigeons, and the little “postmen” flew even faster. In four months about 156,000 letters were sent by them.

　　Now pigeons are still used. This is because sometimes only the little pigeon can carry the message where it is difficult for man to go. That is why pigeons are called “postmen” with feathers.

(1) What is a pigeon?

[　　]

(2) Which of the following is true?

[　　]

A．Pigeons are our daily postmen.

B．Pigeons can fly as fast as a man-made satellite.

C．Pigeons can not do something special for us.

D．Pigeons can do something special for us.

(3) People in Paris used pigeons to send letters because ________.

[　　]

A．they could not send them themselves

B．they could not fly as fast as pigeons

C．they knew pigeons could fly faster than hawks

D．they liked pigeons better than any other animal

(4) How many letters did pigeons send per month according to the text?

[　　]

(5) People call pigeons “postmen” with feathers because ________.

[　　]

A．they are really very good postmen

B．they are birds but can do the job well as postmen

C．they are postmen who can fly and have feathers

D．they have feathers just like postmen

— I can’t get through to the general manager’s office.
—The line is busy. Someone ________ the telephone.