15.When a big boat,like a cruise ship,goes through the ocean,it often creates waves.This happens when the large engines on the back of the cruise ship cause the water on the ocean's surface move up and down violently.These waves move out from the boat in both directions.If you are captaining a smaller boat,you'd better steer clear of a ship's wake,so that your boat is not surfing on the waves,causing it to overturn.
A wave is a pattern of motion.When you look at a wave,it may appear as simply water moving across the surface of the ocean.In fact,this is false.The water is actually not moving in the same direction as the wave.While the wave itself-the pattern of motion-is moving across the surface of the ocean,the water is actually moving in a circular motion,which brings the water molecules back to their original position.The water merely gives the appearance of moving forward.
If this is confusing,think of the kind of wave you do at a baseball stadium.Viewed from a distance,the wave is clearly moving across the stadium.But the thing that makes up the wave-the people-are not moving across the stadium,they're just moving up and down in their seats.This is just like the water in an ocean wave.A lot of water is moving up and down,which gives water the appearance of moving along with the wave.
Surfers pay a lot of attention to waves.If you're not in an area where the waves are suitable for surfing,then you can't surf.Usually,surfers gather in areas known for big waves-waves that rise high off the ocean's surface.If the wave is bigger,then the surfer is often able to surf for longer distances and perform more tricks.The height of a wave is known as its amplitude.If you could make a wave freeze,then you could measure the wave's amplitude by running a tape measure from the ocean's surface to the very peak of the wave.
All waves can be measured using amplitude and wavelength.While the waves created by a boat have very small amplitude-sometimes as small as a few centimeters-the wavelength can be very short,as lots of waves are being generated.By contrast,a tsunami has very high amplitude,sometimes more than 100 feet,but a relatively long wavelength,as it's a high wave.
Waves generated in the same way can have great differences in amplitude and wavelength.For example,think back to the cruise ship.While each ship creates waves caused by the movement of the boat,the properties of each of the waves may be very different.For example,a larger cruise ship,with powerful engines,may create a wave that has high amplitude and a short wavelength.However,if the ship's engines slow down,they may then start creating less powerful waves at a slower rate.This would cause the waves'amplitude to decrease,but its wavelength to increase.
61.What does the phrase"steer clear of a cruise ship's wake"in the 1st paragraph mean?D
A.Keeping awake while steering a ship.
B.Getting a clear view of what is ahead.
C.Following the cruise ship very closely.
D.Keeping away from the cruise ship.
62.The author gives an example of wave people do in the stadium in order toC.
A.illustrate how excited people are in a basketball stadium
B.clear the confusion over measuring the wave's amplitude
C.explain why the water appears to move along the waves
D.demonstrate how to make waves in a basketball stadium
63.The last paragraph gives us the impression thatC.
A.the wave's amplitude may vary,but its wavelength remain the same
B.the amplitude of a wave depends on the direction the water moves forward
C.the more powerful the ships'engines are,the higher the waves they generate
D.measuring the amplitude and wavelength of waves is not quite easy
64.What is this passage mainly about?D
A.What makes the sea water move forwards.
B.How to steer a cruise ship in the rough sea.
C.Why people create waves in the stadium.
D.How waves are created and measured.
分析 本文是一篇科教類閱讀,屬于說明文,當一艘像游輪這樣的大船穿過海洋時,經(jīng)常會產(chǎn)生波浪.當游輪背面的大型引擎使海洋表面的水猛烈地上下移動時,就會發(fā)生這種情況.本文以此展開,主要講述了波浪是如何產(chǎn)生和度量的.
解答 61.D.詞義猜測題.根據(jù)上下文內(nèi)容可知,If you are captaining a smaller boat,you'd better steer clear of a ship's wake,so that your boat is not surfing on the waves,causing it to overturn.句意為如果你擁有一條較小的船,你最好遠離游輪,讓你的船不會在海浪上沖浪,導致它翻船.故 steer clear of a ship's wake意為遠離游輪.故選D.
62.C.細節(jié)理解題.根據(jù)A lot of water is moving up and down,which gives water the appearance of moving along with the wave.可知,作者舉例是為了解釋為什么水似乎沿著海浪移動.故選C.
63.C.推理判斷題.根據(jù)For example,a larger cruise ship,with powerful engines,may create a wave that has high amplitude and a short wavelength.However,if the ship's engines slow down,they may then start creating less powerful waves at a slower rate.This would cause the waves'amplitude to decrease,but its wavelength to increase.可知,本段告訴我們了船舶發(fā)動機越強大,它們產(chǎn)生的波浪越高.故選C.
64.D.主旨大意題.閱讀全文,根據(jù)全文內(nèi)容可知,本文主要講述了波浪是如何產(chǎn)生和度量的.故選D.
點評 本文是一篇科教類閱讀,題目涉及多道主旨大意題,細節(jié)理解題,推理判斷題.做題時學生應仔細閱讀原文,把握文章主要內(nèi)容,聯(lián)系文章上下文內(nèi)容并結合所給選項含義,從中選出正確答案,一定要做到有理有據(jù),切忌胡亂猜測.