下面有3篇短文,每篇短文后有5道题。请根据短文内容,为每题确定1个最佳选项。 第一篇
Renewable Energy Sources
Today petroleum(石油)provides around 40% of the world's energy needs,mostly fuelling automobiles.Coal is still used,mostly in power stations,to cover one-quarter of our energy needs,but it is the least efficient,unhealthiest and most environmentally damaging fossil fuel(矿物燃料).Natural gas reserves could fill some of the gap from oil,but reserves of that will not last into the 22nd century either.Most experts predict we will exhaust easily accessible reserves within 50 years.Less-polluting renewable energy sources offer a more practical long-term energy solution.\to the fact that these resources are not used faster than they can be replaced.
Hydroelectric(水力发电的)power is now the
most
common
form
of
renewable of
world
energy,supplying
around
20%
electricity.China's Three Gorges Dam is the largest ever.At five times the size of the US's Hoover Dam,its 26 turbines(涡轮机)will generate the equivalent energy of 18 coal-fired power stations.It will satisfy 3% of China's entire electricity demand.
In 2003,the first commercial power station to use tidal(潮汐的)currents in the open sea opened in Norway.It is designed like windmill(风车),but others take the form of turbines. As prices fall,wind power has become the fastest
growing
type
of
electricity
generation-quadrupling(翻两番)worldwide between 1999 and 2005.Modern wind farms consist
of
turbines
it
that will
be
generate more
electricity.Though
expensive,there is more than enough wind to provide the world's entire energy needs.Wind farms come in onshore and offshore forms.They can often end up at spots of natural beauty,and are often unpopular with residents.And turbines are not totally harmless-they can interfere with
radar,alter climate and kill sea birds.Scotland is building Europe's largest wind farm,which will power 200,000 homes.The UK's goal is to generate one-fifth of power from renewable sources,mainly wind,by 2020.But this may cause problems,because wind is unreliable.
31.According to the passage,which of the following is the most polluting energy resource? A.Petroleum. B.Coal. C.Natural gas D.Water.
32.China's Three Gorges Dam
A.is the first hydroelectric dam in the world. B.is of the same size as the US's Hoover Dam.
C.can generate around 3% of world electricity.
D.is the largest hydroelectric dam in the world.
33.Which country took the lead in making use of tidal currents to produce power in 2003?
A.The UK. B.China. C.Norway. D.The US.
34.One of the problems with wind farms is that
A.there is not enough wind. B.wind is not reliable.
C.they can only be built on the sea. D.they might influence the world economy. 35.According to the passage,resources like wind are A.renewable. B.recyclable. C.damaging. D.scarce. 第二篇
Hurricane(飓风)Katrina
A hurricane is a fiercely powerful,rotating(旋转的)form of tropical storm that can be 124 to 1,240 miles in diameter.The term hurricane is derived from Hurican,the name of a native
American storm god.Hurricanes are typical of a calm central region of low pressure between 12 to 60 miles in diameter,known as the eye.They occur in tropical regions.Over its lifetime,one of these can release as much energy as 10,000 nuclear bombs.
The seed for hurricane formation is a cluster(聚集)of thunderstoms over warm tropical waters.Hurricanes can only form and be fed when the sea-surface temperature exceeds 27℃ and the surrounding atmosphere is calm.These requirements are met between June and November in the northern part of the world.
Under these conditions,large quantities of water evaporate(蒸发)and condense(冷凝)into clouds and rain-releasing heat in the process.It is this heat energy,combined with the rotation of the Earth,that drives a hurricane. When the warm column of air from the sea surface first begins to rise,it causes an area of low pressure.This in turn creates wind as air is