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Canvas sails,when not in use,may be damaged if().
A . left in the sunlight
B . stowed wet
C . folded frequently
D . washed with soap and water
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The engine may lose power or slow down during running, when this occurs, the first cause possible may be hot bearings and () of the pistons in the cylinders.
A . crack
B . knocking
C . leaking
D . seizure
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There is a possibility that small vessel,ice and other floating objects may not be()by radar at an adequate range.
A . reflect
B . shown
C . detected
D . defected
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According to the passage, it may soon be possible__________
A . to make something as good as human skin
B . to produce drugs without side effects
C . to transplant human organs
D . to make artificial hearts and eyes
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A diesel engine may be hard to start if the ()
A . air intake is restricted
B . engine is cranked too fast
C . vibration dampener is faulty
D . exhaust back pressure is low
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If this can’t be settled reasonably, it may be necessary to()(诉助武力).
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Multi-year ice is the hardest sea ice and should be avoided if possible. It is recognizable because of what tone to its surface color? ()
A . Greenish
B . Bluish
C . Grey
D . Grey-white
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If it becomes necessary for a stand-on vessel to take action to avoid collision,she shall NOT,if possible,()
A . decrease speed
B . increase speed
C . turn to port for a vessel on her own port side
D . turn to starboard for a vessel on her own port side
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A fire pump may be used for other purposes if().
A . the other services are run off a reducing station with a pressure gage
B . one of the required pumps is kept available for use on the fire main system at all times
C . no relief valves are installed
D . all of the above conditions are met
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If a hydraulic pump is overheating, the cause may be ().
A、excessive internal leakage in the pump
B、low discharge pressure and fluid flow
C、excessive fluid level in the hydraulic reservoir
D、operation of the pump at 100% efficiency
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If the Certificate of Inspection of a damaged tank barge has expired,which certificate may be issued to allow its movement to a repair facility? ()
A . Change of employment
B . Permit to proceed
C . Application for inspection
D . Temporary Certificate of Inspectio
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If there has been a fire in a closed unventilated compartment it may be unsafe to enter because of ().
A . unburned carbon particles
B . excess nitrogen
C . a lack of oxygen
D . excess hydroge
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(), remedies must be taken to stop it as early as possible.
A . Any surge occurs
B . Any surge occurred
C . Should any surge occur
D . Should any surge occurring
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原文:Remember you may be taken to court for not doing so, and you may be fined if you cannot prove to the court that you have been excused from wearing it.译文:注意你如果不这么做(系安全带)的话,你有可能被告上法庭,而且你有可能被处以_______,除非你能证明你有不带安全带的理由.
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Great care should be taken to make sure the task is in line with the ______ ability to deal with the task. If the task is too easy, the students may think it is childish and thus lose interest.
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If D/A is possible, it will help ease the _____ problem.
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Most young people enjoy some form. of physical activity. It may be walking, cycling or swimming, in winter, or skating or skiing. It may be a game of some kind -- football, hockey, golf or tennis. It may be mountaineering.
These who have a passion【C1】______climbing high and difficult mountains are often【C2】______with astonishment. Why are men and women【C3】______to suffer cold and hardship, and to【C4】______on high mountains? This astonishment is caused, probably, by the difference between mountaineering and other forms of activity【C5】______which men give their leisure.
Mountaineering is a sport and not a game. There are no man-made rules, as there are for【C6】______games as golf and football. There are, of course, rules of different kinds which it would be dangerous to【C7】______, but it is this freedom from man-made rules【C8】______makes mountaineering attractive to many people. Those who climb mountains are free to use their own【C9】______.
If we【C10】______mountaineering with other more familiar sports, we might think that one big difference is【C11】______mountaineering is not a" team work". We should be mistaken in this. There are it is true , no" matches"【C12】______"teams" of climbers, but when climbers are on a rock face linked by a rope on which their lives may【C13】______, there is obviously teamwork.
A mountain climber knows that he may have to fight forces that are stronger and more powerful than man. He has to fight【C14】______of nature. His sport requires high mental and【C15】______qualities.
A mountain climber【C16】______to improve in skill year after year. A skier is probably past his best by the age of thirty, and most international tennis champions【C17】______in their early twenties. But it is not【C18】______for men of fifty or sixty to climb the highest mountains in the Alps. They may take more【C19】______than younger men, but they probably climb with more skill and less【C20】______of effort, and they certainly experience equal enjoyment.
【C1】
A.for
B.in
C.to
D.of
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It would be very much appreciated if you could confirm the shipping arrangement as soon as possible.
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A meager diet may give you health and long life, but it's not much fun—and it might not even be necessary. We may be able to hang on to most of that youthful vigor even if we don't start to diet until old age.
Stephen Spindler and his colleagues from the University of California at Riverside have found that some of an elderly mouse's liver genes can be made to behave as they did when the mouse was young simply by limiting its food for four weeks. The genetic rejuvenation won't reverse other damage caused by time for the mouse, but could help its liver metabolize drugs or get rid of toxins.
Spindler's team fed three mice a normal diet for their whole lives, and fed another three on half-rations. Three more mice were switched from the normal diet to half-feed for a month when they were 34 months old—equivalent to about 70 human years.
The researchers checked the activity of 11,000 genes from the mouse livers, and found that 46 changed with age in the normally fed mice. The changes were associated with things like inflammation and free radical production—probably bad news for mouse health. In the mice that had dieted all their lives, 27 of those 46 genes continued to behave like young genes. But the most surprising finding was that the mice that only started dieting in old age also benefited from 70 percent of these gene changes.
"This is the first indication that these effects kick in pretty quickly," says Huber Warner from the National Institute on Aging near Washington, D.C..
No one yet knows if calorie restriction works in people as it does in mice, but Spindler is hopeful. "There's attracting and tempting evidence out there that it will work," he says.
If it does work in people, there might be good reasons for rejuvenating the liver. As we get older, our bodies are less efficient at metabolizing drugs, for example. A brief period of time of dieting, says Spindler, could be enough to make sure a drug is effective.
But Spindler isn't sure the trade-off is worth it. "The mice get less disease, they live longer, but they're hungry," he says. "Even seeing what a diet does, it's still hard to go to a restaurant and say: 'I can only eat half of that'."
Spindler hopes we soon won't need to diet at all. His company, Life Span Genetics in California, is looking for drugs that have the effects of calorie restriction.
According to the passage, which of the following is NOT true?
A.Eating less than usual might make us live longer.
B.If we go on a diet when old, we may keep healthy.
C.Dieting might not be needed. ~
D.We have to begin dieting from childhood.
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If something is__________ ,there may not be enough for those who want or need it.
A.rare
B.spare
C.scarce
D.share
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听力原文:A book may be compared to your neighbor; if it's good, it can not last too long; if bad, you can not get rid of it too early.
(29)
A.It is good to have a nice neighbor as long as possible, and it is bad to get rid of a nasty neighbor.
B.You never get tired of a good book; while you should get rid of a bad one the earlier the better.
C.It is good to have a nice neighbor as long as possible, and a bad neighbor as short as possible.
D.A good book is a good neighbor who will last long, and a bad one is just like a bad neighbor who would like to get rid of you.
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听力原文:The trouble is that when things seem to go wrong, it may be too late to fix them, because you actually built the problem in from the start. It's vital that each member of the team knows exactly what it is he or she is supposed to contribute. You won't get a good whole if the parts aren't put together properly. If members are from different departments, they'll have different expectations, which need to be dealt with.
(21)
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When traveling, it is possible that you may be advised to take the travelers' checks, which provide a secure ________ to carrying your money in cash.
A.selection
B.preference
C.alternative
D.substitute
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If it is not dark enough, or too noisy, this may cause difficulty in sleeping. Eating shortly before going to bed may also be responsible for insomnia