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One of the differences between a two-stroke engine and a four-stroke engine is,（）
A . a two-stroke engine can’t work without cylinders
B . a two-stroke engine can’t work without pistons
C . a two-stroke engine can’t work without crankshafts
D . a two-stroke engine can’t work without a blower
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Scavenging in a turbocharged, four-stroke/cycle diesel engine is accomplished（）
A . during the valve overlap period
B . with only the exhaust valve open
C . at a pressure below atmospheric
D . without cooling the cylinders or pisto
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A two-stroke diesel engine exhaust temperature will be lower than a four-stroke diesel engine of the same displacement because the （） (1) MEP is lower and the scavenging air is cooling the exhaust gases (2) valve overlap in a four-stroke
A . (1) only is correct
B . (2) only is correct
C . both (1) and (2) are correct
D . Neither (1) or (2) are correct
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According to the principle of four stroke diesel engine, what is the number of its efficient work stroke per revolution?（）
A . 1/2
B . 1
C . 2
D . 3
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According to the principle of two stroke diesel engine, what is the number of its efficient work stroke per revolution?（）
A . 1/2
B . 1
C . 2
D . 3
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During the suction stroke, the piston is moving （）.
A . inwards
B . outwards
C . downwards
D . upward
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A disadvantage of a four-stroke/cycle diesel engine is （）
A . higher working temperature of piston and cylinder
B . the use of scavenge ports
C . fewer power strokes per revolution of the crankshaft
D . part of the fuel is burned as the piston is moving away from top dead center
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In the suction stroke air is induced into the cylinder （）In the compression stroke the air is compressed.
A . by an fuel valve
B . through an inlet valve
C . with an exhaust valve
D . from an outlet valve
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She was not really ________ by this way of reasoning.
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The dishes of this restaurant can really its reputation.
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“Although your ribs are sore from laughing too much, you really need to compete this weekend” is a compound sentence.
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I think this is really the ideal college for me.
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“This is really—really—disappointing.”
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If you can speak really fast with few pauses, this means you can speak really fluently.
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From the conversation, we know that Eve really appreciates the vivid description of ( ) in this novel.
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With this method, you can produce really designs with the simplest machines.
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折,in English, is horizontal stroke with a vertical turn.
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听力原文：W: Maybe we should take Main Street this morning. The radio announcer said traffic on the 7th Avenue is really heavy.
M: Well, if he says to take Main Street, we should go the other way!
Q: What do we learn about the man？
(18)
A．He always does what the announcer says.
B．He thinks that the announcer is very good at his work.
C．He is angry at the announcer's words.
D．He doesn't believe what the announcer says.
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How many really suffer as a result of labor market problems？ This is one of the most critical yet contentious social policy questions. In many ways, our social statistics exaggerate the degree of hardship.
Unemployment does not have the same dire consequences today as it did in the 1930's when most of the unemployed were primary breadwinners, when income and earnings were usually much closer to the margin of subsistence, and when there were no countervailing social programs for those failing in the labor market. Increasing affluence, the rise of families with more than one wage earner, the growing predominance of secondary earners among the unemployed, and improved social welfare protection have unquestionably mitigated the consequences of joblessness. Earnings and income data also overstate the dimensions of hardship. Among the millions with hourly earnings at or below the minimum wage level, the overwhelming majority are from multiple-earner, relatively affluent families. Most of those counted by the poverty statistics are elderly or handicapped or have family responsibilities which keep them out of the labor force, so the poverty statistics are by no means an accurate indicator of labor market pathologies.
Yet there are also many ways our social statistics underestimate the degree of labor-market- related hardship. The unemployment counts exclude the millions of fully employed workers whose wages are so low that their families remain in poverty. Low wages and repeated or prolonged unemployment frequently interact to undermine the capacity for self-support. Since the number experiencing joblessness at some time during the year is several times the number unemployed in any month, those who suffer as a result of forced idleness can equal or exceed average annual unemployment, even though only a minority of the jobless in any month really suffer. For every person counted in the monthly unemployment tallies, there is another working part-time because of the inability to find full-time work, or else outside the labor force but wanting a job. Finally, income transfers in our country have always focused on the elderly, disabled, and dependent, neglecting the needs of the working poor, so that the dramatic expansion of cash and in-kind transfers does not necessarily mean that those failing in the labor market are adequately protected.
As a result of such contradictory evidence, it is uncertain whether those suffering seriously as a result of thousands or the tens of millions, and, hence, whether high levels of joblessness can be tolerated or must be countered by job creation and economic stimulus. There is only one area of agreement in this debate--that the existing poverty, employment, and earnings statistics are inadequate for one of their primary applications, measuring the consequences of labor market problems.
Which of the following is the principal topic of the passage？ ______
A．What causes labor market pathologies that result in suffering.
B．Why income measures are imprecise in measuring degrees of poverty.
C．Which of the currently used statistical procedures are the best for estimating the incidence of hardship that is due to unemployment.
D．How social statistics give an unclear picture of the degree of hardship caused by tow wages and insufficient employment opportunities.
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By saying "Let‘s hope that this time it really will be the last one"， the father meant that 查看材料
A.he hoped there would be no more wars in the world
B.he wished the Second World War had not happened
C.he hoped people would build more bonfires
D.he wished people would learn many lessons from the war
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To average people, they often tend to live under the illusion that English often means a good opportunity for one’s career, is this really the case？.（英译中)
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It is hard to predict how science is going to turn out, and if it is really good science it is impossible to predict. If the things to be found are actually new, they are by definition unknown in advance. You cannot make choices in this matter. You either have science or you don't, and if you have it you are obliged to accept the surprising and disturbing pieces of information, along with the neat and promptly useful hits,
The only solid piece of scientific truth abut which I feel totally confident is that we are profoundly ignorant about nature. Indeed, I regard this as the major discovery of the past hundred years of biology. It is, in its way, an illuminating piece of news. It would have amazed the brightest minds of the 18th. century Enlightenment to be told by any of us how little we know and how bewildering seems the way ahead. It is this sudden confrontation with the depth and scope of ignorance that represents the most significant contribution of the 20th century science to the human intellect. In earlier times, we either pretended to understand how things worked or ignored the problem, or simply made up stories to fill the gaps. Now that we have begun exploring in earnest, we are getting glimpses of how huge the questions are, and how far from being answered. Because of this, we are depressed. It is not so bad being ignorant if you are totally ignorant; the hard thing is knowing in some detail the reality of ignorance, the worst spots and here and there the not-so-bad spots, but no true light at the end of the tunnel nor even any tunnels that can yet be trusted.
But we are making a beginning, and there ought to be some satisfaction. There are probably no questions we can think up that can' t be answered, sooner or later, including even the matter of consciousness. To be sure, there may well be questions we can't think up and therefore limits to the reach of human intellect, but that is another matter. Within our limits, we should be able to work our way through to all our answers, if we keep at it long enough, and pay attention.
According to the author, really good science ______.
A．would surprise the brightest minds of the 18th century Enlightenment
B．will help people to make the right choice in advance
C．will produce results which cannot be foreseen
D．will bring about disturbing results
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The equipment is not really__（）
A．capable
B．evident
C．possible
D．mobile
