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The （） pump discharges a nearly constant amount of liquid regardless of pressure.
A . mixed-flow
B . axial-flow
C . centrifugal
D . displacement
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近点（near point of vision）
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Gear pumps are （） type because they discharge a near constant amount of liquid regardless of pressure.
A . positive displacement
B . non-positive displacement
C . mixed-flow
D . axial-flow
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Nearly（）of the land in Canada has no permanent population.
A . half
B . two-thirds
C . 89%
D . 95%
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The chassis of 15 trucks are rust-stained，particularly（）near the mast house.
A . such
B . this
C . these
D . those
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Above-normal tides near the center of a hurricane maybe caused by the （）.
A . high barometric pressure
B . jet stream
C . storm surge
D . torrential rai
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The （） discharge a nearly constant amount of liquid regardless of pressure.
A . mixed-flow pump
B . axial-flow pump
C . centrifugal pump
D . displacement pum
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The Blitz radically changed the face of London for the first time since（）nearly 3 centuries earlier.
A . the Black Death
B . the Great Fire
C . the Civil War
D . the Great Plague
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When your vessel is on or near the path of an approaching tropical storm the（）.
A . wind direction remains steady
B . wind speed increases
C . barometer falls
D . All of the above
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During working, when the piston is near the （）, the air ignites the fine spray of fuel.
A . TDC
B . DTC
C . BDC
D . BCD
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Above-normal tides near the center of a hurricane maybe caused by the（）.
A . high barometric presure
B . jet stream
C . storm surge
D . torrential rai
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Which of the following is not the major themes in Dickinson's poetry?
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We have recovered or nearly recovered from the symptoms of _________.
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According to recent survey, nearly 90% of domestic citizens _______this motion.
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Plastic is the panacea of the ages. Nearly every man-made object （1)_____ （2)_____ of, or
Plastic is the panacea of the ages. Nearly every man-made object (1)_____ (2)_____ of, or at least (3)_____ its very structure, to this wonder compound. Rain slickers, computer terminals, automobile engine parts, coffee cups (and the sugar stirrers too), breast implants, toy soldiers—they are all made up of plastic, or one of its many (4)_____ Since the (5)_____ of civilization, humankind bas been experimenting (6)_____ a multifunctional material—one that had to be equally strong and lightweight—to carry, contain and protect valuables. (7)_____ it could carry, contain and protect humans too, even better. Generations of tinkerers and scientists set off (8)_____ the challenge, striking gold some 170 years ago. By mixing natural rubber with sulphur they created the world's most utilized material ever. In developing a (9)_____, malleable and durable substance, the most important inventions of the industrial age were to follow shortly thereafter. The automobile and airplane industries, to (10)_____ just two, owe their very existence to plastic. And, (11)_____ celluloid plastic strips, the Lumiere Brothers would never have brought moving pictures to the big screen.
The development of plastic is a story of human (12)_____, ingenuity and luck. (13)_____ the legend now goes, in 1839, the American inventor Charles Goodyear (the famous tyre company would later use his name) was experimenting with the sulphur treatment of natural rubber when he dropped a piece of sulphur-treated rubber on a stove. The heat seemed to give rubber (14)_____ properties. It was stronger, more (15)_____ to abrasions more elastic, much less (16)_____ to temperature, (17)_____ to gases, and highly resistant to chemicals and electric (18)_____ Eyeing this as a cheaply and easily reproduced construction material, a whirlwind of work (19)_____ and the birth of (20)_____ plastic and plastic-derivatives were born from camphor to celluloid to rayon; cellophane, polyvinyl chloride (or PVC); styrofoam and nylon were soon to follow.
A．consists
B．comprises
C．constitutes
D．composes
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What is Dickinson's particular form. of self-publication？
A．She ran her own publishing house.
B．She wrote her poems in her letters.
C．She wrote to newspapers regularly.
D．She recorded her poems in her diary.
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To many web-building spiders, most of 【C1】______are nearly blind, the web is their essenti
To many web-building spiders, most of 【C1】______ are nearly blind, the web is their essential window 【C2】______ the world: their means of communicating, 【C3】______ prey, meeting mates and protecting themselves. A web-building spider 【C4】______ its web is like a man marooned on an island of solid rock, totally out of touch and destined to starve to death. So 【C5】______ is the web to an orb-web spider's survival that the animal will continue to construct new webs daily 【C6】______ it is being starved.
For 16 days the 【C7】______ spider builds completely normal webs. Then, as the animal gets scrawnier, it constructs a wider-meshed web using 【C8】______ strands. Such webs would only trap larger prey, which is more 【C9】______ from the perspective of a starving spider.
The spider 【C10】______ energy by recycling web protein. It simply eats its own web each evening and reuses it to manufacture 【C11】______ silk. In studies with radioactively labeled materials, it 【C12】______ that 95 percent of web protein reappeared in 【C13】______ web. Most of the energy needed for web-building is used in walking over the strands as they are laid down.
Scientists are 【C14】______ by the adaptability of the spider's highly preprogrammed brain, which is larger 【C15】______ its size than the brain of any other invertebrate. If web-building is interrupted, or if some of the 【C16】______ strands are destroyed, the spider 【C17】______ retraces its steps to see where the web is 【C18】______ and then finishes building a 【C19】______ web. One spider will even finish building the incomplete web of 【C20】______ .
【C1】
A．them
B．whom
C．that
D．which
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Our part of the mission is nearly complete and the new crew will for us.
A、take over
B、take out
C、take off
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In paragraph 1, "... the number of loans originated increased by nearly fourfold" means______.
A．the amount of money owed is four times higher than before
B．four times as many students have loans than before
C．there are four times as many loans as before
D．four times as many loans are applied for than before
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After being tested in many ways， this newly-designed machine will________in the near future.
A.take place
B.put into use
C.come into use
D.take action
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How many years will it be before the world runs out of oil？ The question is far from an academic exercise. This year oil hit a near record high of $40 a barrel, and Royal Dutch/Shell Group downgraded its reserves by 4.5 billion barrels.
While consumers pay for perceived shortages at the pump, scientists and economists struggle to reach consensus over "proven oil reserves," or how much oil you can realistically mine before recovery costs outstrip profits. Economist Leonardo Maugeri fired up the debate that accused the "oil doomsters" of crying wolf.
Oil pessimists estimate that maximum oil production around the globe will peak in 2008 as demand rises from developing economies such as China. "If you squeezed all the oil in Iraq into a single bottle, you could fill four glasses, with the world consuming one glass of oil each year," says a physicist. "We've consumed nine bottles since oil was discovered, and we have another 9 or 10 in the refrigerator. How many more are there？ Some say five or six, but we say three."
Others believe, like Maugeri, that the number of glasses is virtually limitless. John Felmy, chief economist at the American Petroleum Institute, argues that peak oil-production estimates are so far off that. "Ever since oil was first harvested in the 1800s, people have said we'd run out of the stuff," Felmy says. In the 1880s a Standard Oil executive sold off shares in the company out of fear that its reserves were close to drying up. Some scientists said in the 1970s that we'd hit peak oil in 2003. It didn't happen.
If there is an end to the debate, advanced oil-recovery technologies will most likely find it. A new seismic survey technique, for instance, sends sound waves of varying frequencies thousands of meters belowground. Microphones arrayed aboveground record the reflected signals, and computer software models a 3-D portrait of possible oil hot spots. The surveys have now added a fourth dimension, creating a time-lapse simulation of fluid movements.
Companies are also finding sophisticated ways to mine more oil from existing wells. Flexible, coiled-tube drills that carve out horizontal side paths are a marked improvement over conventional, rigid drills that move only straight down. Using such technology, companies hope to soon harvest 50 to 60 percent of oil from existing wells, up from today's 35 percent.
Biotechnology, too is keeping the black gold flowing. University of Albert scientists are searching for microorganisms that could dilute viscous, hard-to-recover oil and make it flow more freely.
"Technology can help push peak oil production further and further out," says an expert. But only time will tell when oil production will peak.
According to the passage, which of the following statements is true？
A．How long the oil age will last is simply an academic question.
B．The oil price this year set a new record.
C．Shell Group reduced its reserves to 4.5 billion barrels this year.
D．Economists disagree with one another on how much oil you can realistically mine.
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Building a house costs quite a lot of money. Suppose you plan to build a house. Your first step is to find a right piece of land. Your choice(选择) will depend on many different things. You will probably try to find a sunny place with pleasant surroundings(环境) near shops and bus stops not too far from your friends and the place where you work.
Next you will find a good builder and together with the builder you will work out a plan. The builder will draw the plan. It will show the number of rooms their position and size and other parts such as windows doors and electric outlets(电插座). The builder will work out how much money is needed to build your house. He will work out the cost of the wood bricks the glass and everything else that must be used in building the house. Later on when he starts to build this estimate(预算) must be corrected and revised(修订). His estimate is based on existing prices but prices of such things may change and many other things may happen between the time when he makes the estimate and the time when he builds the house.
When the builder gives his estimate you may wish to change your plan. (You may also wish to change your builder if his estimate is too high!) You may find that the house you wanted at first costs too much or that you can spend a little more and add something to your plan. The builder&39;s estimate depends on the plan but the final plan depends on the builder&39;s estimate.
1.The best title of this passage is_______.
A.Building a House Costs Much Money
B.Estimate Is Important
C.Planning a House
D.Depend on the Builder
2.The first thing for a person to build a house is_______.
A.to get as much money as possible
B.to find a suitable piece of land
C.to work out a plan
D.to make an estimate
3.The underlined phrase "draw the plan" in this passage means_______.
A.drawing a picture of a building or a room
B.making a plan
C.working out a solution
D.taking a picture out of a room
4.What is the relationship(关系) between the estimate and the plan？
A.The plan depends on the estimate.
B.The estimate depends on the plan.
C.The plan has nothing to do with the estimate.
D.The estimate and the plan depend on each other.
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Nearly half of all foreign exchange trading involves banks in_and _（）
A．New York; Frankfurt
B．New York; London
C．London; Frankfurt
D．Tokyo; New York
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The United States grows nearly one seventh of the world's grain and supplies a half
是
否
