66．According to this passage, we can know that the shepherd was ______．
A．patient and brave B．foolish and impolite
C．humorous and intelligent D．knowledgeable and talkative
D
In summer,
millions of people will head for the beach．And while 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? Or
have you jumped in the water and felt the energy as waves crashed over you?”
asked Jamie Taylor of the Wave Energy Group at the University of Edinburgh in
Scotland．“There is
certainly a lot of energy in waves．”
Scientists are
working on using that energy to make electricity．
Most waves are
created when winds blow across the ocean．“The winds start out by making little ripples (波纹) 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 shore, people can set up dams or other barricades to block the
water and send it through a large wheel called a turbine (涡轮) ．The turbine can then power an electrical generator (发电机) ．
The United
States and a few other countries have started doing research on wave energy ,
and it is already being used in Scotland．
The resource is
huge．We will never
run out of wave power, besides, wave energy does not create the same pollution
as other energy sources, such as oil and coal．
Oceans cover
three quarters of the earth’s surface．That would make wave power seem perfect for creating energy around
the world．There are
some drawbacks, however．
Jamie Taylor
said that wave power still cost too much money．He said that its effects on animals in the sea were still unknown．Plus, wave power would get in the
way of fishing and boat traffic．
With more
research, however, “many of these problems might be overcome,” Taylor said．“Demand for energy to power our TVs
and computers, drive our cars, and heat and cool our homes is growing quickly
throughout the world．Finding more energy sources 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 switch, an ocean wave could be providing the
electricity!