大学英语四级模拟试题(6)

　　Questions 31 to 36 are based on the following passage：
　　The focusing or sharpening of the image is performed by a special apparatus.In every camera，the farther the object is from the eye，the farther forward—and the nearer the object is to the eye，the farther backward—is its image thrown.In photographers'cameras，the back is made to slide，and can be drawn away from the lens when the object that casts the picture near， and pushed forward when it is far.The picture is thus kept always sharp.But no such change of length is possible in the eyeball，and the same result is reached in another way.The lens， namely，grows more convex（凸面的）when a near object is looked at，and flatter when the object recedes.This change is due to the antagonism of the“ciliary muscle（睫状肌）。The ligament（韧带），when the ciliary muscle is at rest，assumes such a spreadout shape as to keep the lens rather flat.But the lens is highly elastic；and it springs into the more convex form which is natural to it whenever the ciliary muscle，by contracting， makes the ligament relax its pressure.The contraction of the muscle，by thus tendering the lens more refractive，adapts the eye for near objects（”accommodatesit for them，as we say）：and its relaxation，by rendering the lens less refractive， adapts the eye for distant vision.Accommodation for the near is thus the more active change，since it involves contraction of the ciliary muscle.When we look far off，we simply let our eyes go passive. We feel the difference in the effort when we compare the two sensation of change.
　　31.In order to focus on distant objects，the lens of the eye ____ .
　　A）becomes more convex B）becomes more active
　　C）becomes more refractive D）flattens
　　32.The ligament，when not acted on by the contraction of the ciliary muscle，____ .
　　A）maintains its pressure on the lens so that the lens remains flat
　　B）relaxes its pressure on the lens so that it remains convex
　　C）maintains its pressure on the lens so that the lens remains convex
　　D）relaxes its pressure on the lens so that it remains flat
　　33.Functionally，we may compare ____ .
　　A）the lens of the camera with the lens of the eye
　　B）the lens of the camera with the ciliary muscle
　　C）the lens of the eye with the sliding of the back of the camera
　　D）the sliding of the back of the camera with the adaptability of the eyeball
　　34.Which of the following activities is most tiring for the lens of the eye？
　　A）Looking at a distant mountain.
　　B）Being a“sidewalk superintendent。
　　C）Watching squirrels being fed.
　　D）Reading a book.
　　35.The tone of this passage can best be described as ____ .
　　A）professionally scientific B）argumentative
　　C）matter of fact and formal D）informal and matter of fact
　　Questions 36 to 40 are based on the following passage：
　　Are you aware that you actually possess six senses？The sixth is a muscular sense responsible for directing your muscles intelligently to the exact extent necessary for each action you perform.For example，when you reach for an object，the sensory nerves linking the muscles to the brain stop your hand at the correct spot.This automatic perception of the position of your muscles in relation to the object is your muscular sense in action.
　　Muscles are stringy bundles of fibers varying from one five thousandth of an inch to about three inches.They have three unique characteristics： they can become shorter and thicker；they can stretch；and they can retract to their original po- sition.Under a high-powered microscope，muscle tissue is seen as long，slender cells with a grainy texture like wood.
　　More than half of a person's body is composed of muscle fibers，most of which are involuntary，in other words，work without conscious direction.The voluntary muscles，those that we move consciously to perform particular actions，number more than five hundred.Women have only 60 to 70 percent as much muscle as men for their body mass.That is why an average woman can't lift as much，throw as far，or hit as hard as an average man.
　　36.According to the selection，more than half of a person's body is composed of ____ .
　　A）involuntary muscles B）muscle fibers
　　C）sensory nerves D）voluntary muscles
　　37.Intelligent use of the muscles means that ____ .
　　A）one improves muscular action consciously
　　B）one always knows what his muscles are doing
　　C）one's muscles are used only to the extent necessary for each action they perform
　　D）one perform simple actions without working
　　38.An average woman is weaker than an average man because she has ____ .
　　A）60to 70percent less muscle for her body mass
　　B）only 60to 70percent as much musc1e for her body mass as an average man
　　C）less muscle fiber for her body weight
　　D）more voluntary muscles than an average man
　　39.Which of the following statements is implied but not stated？
　　A）Muscular sense involves automatic perception.
　　B）There are more than 500involuntary muscles in the body.
　　C）Muscle tissue is inflexible.
　　D）The muscular sense is more important than any other sense.
　　40.According to the passage，the muscular sense is responsible for ____ .
　　A）the normal breathing function
　　B）the work of only our voluntary muscles
　　C）directing our muscles intelligently
　　D）the efficiency of our muscles
　　Part III Vocabulary and Structure（20 minutes）
　　Directions：There are 30incomplete sentences in this part.For each sentence there are four choices marked A），B），C）and D）。Choose the ONE that best completes the sentence.Then mark the corresponding letter on the Answer Sheet with a single line through the centre.
　　4l.By the time jet aircraft could fly at a speed faster than sound，train transportation in the United States ____ over several decades.
　　A）was declining B）had been declining
　　C）has declined D）declined
　　42.Had Australia not been colonized by the British，English ____ there now.
　　A）will not be spoken B）is not spoken
　　C）would not have been spoken D）would not be spoken
　　43.I should like to rent a house，modern，comfortable and ____ in a quiet environment.
　　A）before all B）first of all
　　C）after all D）above all
　　44.This ____ was conducted to find out how many people prefer butter.
　　A）examination B）inspect C）survey D）analysis
　　45.There are some hobbies that can only be by people with plenty of time and money.
　　A）taken on B）taken over C）taken up D）taken in
　　46.He gave much attention and thought to his children.
　　A）looking out B）keeping up C）bringing up D）making out
　　47.It is estimated that the engine of this model is as twice powerful as the ____ one.
　　A）prior B）early C）former D）previous
　　48.His parents ____ of me whether we adapted to the new college life.
　　A）investigated B）knew C）heard D）inquired
　　49.Before leaving his office，the manager showed no sign of ____ our proposals.
　　A）bringing about B）showing off
　　C）responding D）pointing out
　　50.Please keep ____ about what you have just heard.
　　A）quiet B）still C）silent D）voiceless
　　51.We shall not succeed in controlling world population ____ we improve living conditions.
　　A）as B）unless C）while D）if
　　52.Candidates who wish to ____ from the examination must notify the secretary immediately.
　　A）resign B）remove C）suspend D）withdraw
　　53.I never expect you to ____ at the meeting.I thought you were abroad.
　　A）turn on B）turn out C）turn up D）turn off
　　54.The cost of the operation will need to be ____ very precisely.
　　A）carried out B）cut out C）filled out D）figured out
　　55.It was not until he had arrived home that he remembered not to be ____ that the safe was locked.
　　A）confirmed B）believed C）told D）assured
　　56.This company has decided to ____ its main office from Hong Kong to Pudong Development Zone in Shanghai.
　　A）transfer B）transform C）transplant D）transport
　　57.He will first explain the items of the contract to you and then you can discuss it ____ .
　　A）in particular B）for detail C）in addition D）at length
　　58.According to Nobel's famous will，the interest on his fund will be ____ to those who have made the greatest contributions to mankind during the previous year.
　　A）devoted B）distributed C）reserved D）assisted
　　59.The Americans and the British not only speak the same language but also ____ a large number of social customs.
　　A）share B）join C）take D）make
　　60.Everyone else was killed in the accident.I was the only one to ____ .
　　A）relieve B）alive C）release D）survive
　　61.Susan never laughed loudly，____ lose her temper.
　　A）or she ever did B）or did she ever C）nor did she ever D）nor she ever did
　　62.It is decided that no smoking ____ in the cinema.
　　A）is allowed B）be allowed
　　C）will be allowed D）should have been allowed
　　63.The size of the audience，I had expected，was well over three thousand.
　　A）who B）whom C）as D）that
　　64.We got to the station ____ only that the train we had planned to take had just left，so we had to take the coach.
　　A）exhausted；learned B）exhausted；to learn
　　C）exhausting；to learn D）to exhaust；learning
　　65.I told the stranger how to get there but perhaps I ____ him a map.
　　A）should have given B）had to give C）ought to give D）must have given
　　66. ____，all of the soldiers laid down on the ground immediately and could not move their bodies，very tied.
　　A）The task having been finished；felt
　　B）The task having been finished；feeling
　　C）Finished the task；felt
　　D）The task having been finished；having felt
　　67.I need a book dealing ____ anti-pollution problems.
　　A）about B）on C）with D）to
　　68.If Betty sets her mind on something there is nothing to hold her ____ .
　　A）up B）on C）back D）out
　　69.Though his appearance has changed so much，I recognized him the ____ I saw him.
　　A）instantly B）moment C）occasion D）time
　　70.Colour-blind people often find it difficult to ____ between blue and green.
　　A）distinct B）distinguish C）separate D）divide