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Natural gas Vehicles Kermit the Frog once said, "It’’s not that easy bein’’green." Although he wasn’’t referring to cars, his observation seems particularly appropriate for the auto industry today: Designing, developing and marketing "green" cars has not been an easy task, which is why gasoline powered vehicles still rule the road and fossil fuels still account for almost 75 percent of the world’’s energy consumption. As gasoline prices soar and concern over harmful emission mounts, however, cars that run on alternate fuel sources will become increasingly important. A natural-gas vehicle, or NGV, is the perfect example of such a car―it’’s fuel-efficient, environmentally friendly and offers a relatively low cost of ownership. Natural Gas Basics The word "gas" is a confusing term because it is used to describe many different substances that are similar but not exactly the same. For example, the "gas" you put in your car is gasoline, one component of crude oil, or petroleum. Petroleum is a dark, sticky liquid mixture of compounds formed underground by the decay of ancient marine animals. Natural gas also comes from the decay of ancient organisms, but it naturally takes a gaseous form instead of a liquid form. Natural gas commonly occurs in association with crude oil. It is derived from both land plants and aquatic (水生的) organic matter and forms above or below oil deposits. It is often dissolved in crude oil at the high pressures existing in a reservoir. There are also reservoirs of natural gas, known as non-associated gas, that contain only gas and no oil. Natural gas consists primarily of methane (沼气) and other hydrocarbon gases. Hydrocarbons are organic compounds composed only of the elements carbon and hydrogen. The hydrocarbons in natural gas are called saturated hydrocarbons because they contain hydrogen and carbon bound together by single bonds. Like gasoline, natural gas is combustible (易燃的), which means it can be used in a combustion engine like gasoline. But cars that could burn natural gas didn’’t appear on the scene until the 1930s. From Field to Ford We extract natural gas trapped in underground reservoirs by drilling wells into the earth. A modern well, equipped with diamond-studded drill bits, can drill to depths approaching 25,000 feet. Throughout the 19th century, the use of natural gas remained localized because there was ho way to transport large quantities of gas over long distances. In 1890, the invention of a Teak-proof pipeline coupling made it possible to transport gas miles from the source. Improvements in pipeline technology continued over the next two decades until long-distance gas transmission became practical. From 1927 to 1931, laborers constructed more than 10 major natural gas transmission systems in the United States, making natural gas viable energy source for many applications. The oil shortages of the late 1960s and early 1970s "brought renewed interest in natural gas as a fuel source, especially for automobiles! Today, owners of natural-gas vehicles can fill up their cars at one of 1,300 fueling stations located in the United States. Honda also offers a personal natural gas pump to people who purchase its natural-gas-powered Civic. The pump uses a home’’s existing natural gas lines and can be installed for 500 to 1500. Natural-gas Vehicle Design Natural-gas vehicles use the same basic principles as gasoline-powered vehicles. In other words, the fuel (natural gas in this case) is mixed with air in the cylinder of a four-stroke engine and then ignited by a spark plug to move a piston(活塞) up and down. Although there are some differences between natural gas and gasoline in terms of flammability and ignition temperatures. NGVs themselves operate on the same fundamental concepts as gasoline-powered vehicles. Still, some modifications are required to make an NGV work efficiently. These changes are primarily in the fuel storage tank, the engine and the chassis (底盘). Advantages The biggest advantage of NGVs is that they reduce environmentally harmful emissions. Natural-gas vehicles can achieve up to a 93 percent reduction in carbon monoxide emissions, 33 percent reduction in emissions of various oxides of nitrogen and a 50 percent reduction in reactive hydrocarbons when compared to gasoline vehicles. NGVs also rate higher in particulate matter 10 (PM10) emissions. PM10 particles transport and deposit toxic materials through the air. NGVs that operate in diesel applications can reduce PM10 emissions by a factor of 10. Natural-gas vehicles also offer these benefits: NGVs are safer. The fuel storage tanks on an NGV are thicker and stronger than gasoline or diesel tanks. There has not been an NGV fuel-tank rupture in more than two years in the United States. Natural gas costs are lower than gasoline. On average, natural gas costs one-third less than gasoline at the pump. Natural gas is convenient and abundant. A well-established pipeline infrastructure exists in the United States to deliver natural gas to almost every urban area and most suburban areas. There are more than 1 ,300 NGV fueling stations in the United States, and more are being added every day. Natural gas prices have exhibited significant stability compared to oil prices. Historically, natural gas prices have exhibited significant price stability compared to the prices of petroleum-based fuels. This stability makes it easier to plan accurately for long-term costs. NGVs have lower maintenance costs. Because natural gas burns so cleanly, it results in less wear and tear on the engine and extends the time between tune-ups and oil changes. Disadvantages One of the biggest complaints about NGVs is that they aren’’t as roomy as gasoline cars. This is because NGVs have to give up precious cargo and trunk space to accommodate the fuel storage cylinders. Not only that, these cylinders can be expensive to design and build―a contributing factor to the higher overall costs of a Natural-gas vehicle compared to a gasoline-powered car. Another drawback is the limited driving range of NGVs, which is typically about half that of a gasoline-powered vehicle. For example, Honda’’s natural gas Civic, the Civic GX, can go up to 220 miles without refueling. A typical gasoline-powered Civic can go approximately 350 miles without refueling. If a dedicated NGV ran out of fuel on the road, it would have to be towed to the owner’’s home or to a local natural gas refueling station, which might be harder to find than a "regular" gas station. Finally, it should be noted that natural gas, like gasoline, is a fossil fuel and cannot be considered a renewable resource. While natural gas reserves in the United States are still considerable, they are not inexhaustible. Some predict that there are enough natural gas reserves remaining to last another 67.1 years, assuming that the 2003 level of production continues.The basic principles applied to natural-gas vehicles are quite different from those applied to gasoline-powered vehicles. A.YB.NC.NG

The poor man lives in the ___.A. slumB. slimC. slungD. slang

Section C-|||-Directions: There are 2 passages in this section.Each passage is followed by some questions or unfinished statements.-|||-For each of them there are four choices marked A),B),C)and D).You should decide on the best choice and mark the-|||-corresponding letter on Answer Sheet 2 with a single line through the centre.-|||-Passage One-|||-Questions 46 to 50 are based on the following passage.-|||-Financial independence is one of the many markers used to designate the crossover from childhood into young-|||-adulthood,and it`s a milestone most Americans think young adults should reach by the age of 22.But that`s not the reality for-|||-most young adults who`ve reached this age.-|||-The share of young adults who could be considered `financially independent"their parents by their early 20s has-|||-gone down somewhat in recent decades.A new Pew Research Center analysis of f Census Bureau data finds that,in 2018,24%-|||-of young adults were financially independent b age 22 or younger,compared with 32%in 1980.-|||-Looking more broadly at young adults aged 18 to 29,the share who are financially independent has been largely stable-|||-in recent decades.Overall,young men are more likely than young women to be financially independent, but this gender gap-|||-has diminished significan-|||-The new survey findings underscore the extent to which many young adults are financially reliant on their parents.Some-|||-45% of adults aged 18 to 29 say they have received a lot of or some financial help from their parents in the past 12 months.-|||-According to parents of young adults,those shares may be even higher.About six-in-ten parents with children aged 18 to 29-|||-say they have given their kids at least some financial help in the past year.-|||-majority of young adults who have received financial help from their parents say at least some of it was for recurring-|||-expenses.Six-in-ten say the money went toward household expenses such as groceries or bills,and significant shares used it-|||-to pay their tuition,rent or mortgage.-|||-Beyond finantindependence the pace with which young adults are reaching other markers of adulthood has-|||-slowed significantly over the past several decades.Today`s young adults are staying in school longer and are marrying and-|||-establishing their own households later than privers ecnerations.A gro share are living in their parents`homes well-|||-into their 20s and even early 30s.Some of these changes are linked to economic challenges, while others may represent a-|||-rearrangement of goals and priorities.-|||-46.What does the author try to imply in Paragraph 1?-|||-A) Financial independence is vital to being a young adult.-|||-B)Financial indepencencem the start of adulthood.-|||-C)Most young Americans live their life in a unique way.-|||-D) Many American young adults depend on their parents.-|||-47.What is the change between young Americans in 2018 and those in 1980?-|||-A)The latter have more financial knowledge.-|||-B)The latter have less sense of social responsibility.-|||-C)The former are more ambitious than the latter.-|||-D)The former are less financially independent.-|||-48.What do we learn about the age-group of 18 to 29 in the U.S.?-|||-A) Young women are fast catching up with young men financially.-|||-B)Young men are more vulnerable to bankruptcy than young women.-|||-C)The past decade witnessed a dramatic fina change among them.-|||-D)About 45%of them have got financial support from their friends.-|||-49.What do young Americans say about the financial assistance they received from their parents?-|||-A)Most of them say it was used to cover unexpected expenses.-|||-B)More than half of them say it was for household expenses.-|||-C)Many say a great amount of it went toward entertainment.-|||-D)Some say a small share of it was about paying tuition or rent.-|||-50.What is said about the young adults nowadays in the U.S.?-|||-A)The pace with which they reach markers of adulthood is speeding up.-|||-B)An increasing percent of them would like to live separately from their parents.-|||-C)They tend to spend more years in schooling and delay their marriage age.-|||-D)They are more likely to be financially independen after getting married.

Financial independence is one of the many markers used to designate the crossover from childhood into young adulthood, and it's a milestone most Americans think young adults should reach by the age of 22. But that's not the reality for most young adults who've reached this age.The share of young adults who could be considered "financially independent" from their parents by their early 20s has gone down somewhat in recent decades. A new Pew Research Center analysis of Census Bureau data finds that, in 2018, 24% of young adults were financially independent by age 22 or younger, compared with 32% in 1980.Looking more broadly at young adults aged 18 to 29, the share who are financially independent has been largely stable in recent decades. Overall, young men are more likely than young women to be financially independent, but this gender gap has diminished significantly.The new survey findings underscore the extent to which many young adults are financially reliant on their parents. Some 45% of adults aged 18 to 29 say they have received a lot of or some financial help from their parents in the past 12 months. According to parents of young adults, those shares may be even higher. About six-in-ten parents with children aged 18 to 29 say they have given their kids at least some financial help in the past year.A majority of young adults who have received financial help from their parents say at least some ofit was for recurring expenses. Six-in-ten say the money went toward household expenses such as groceries or bills, and significant shares used it to pay their tuition, rent or mortgage.Beyond financial independence, the pace with which young adults are reaching other markers of adulthood has slowed significantly over the past several decades. Today's young adults are staying in school longer and are marrying and establishing their own households later than previous generations. A growing share are living in their parents' homes well into their 20s and even early 30s. Some of these changes are linked to economic challenges, while others may represent a rearrangement of goals and priorities.1 What does the author try to imply in Paragraph 1? ______A.Financial independence is vital to being a young adult.B.Financial independence marks the start of adulthood.C.Most young Americans live their life in a unique way.D.Many American young adults depend on their parents.2 What is the change between young Americans in 2018 and those in 1980? ______E.The latter have more financial knowledge.F.The latter have less sense of social responsibility.G.The former are more ambitious than the latter.H.The former are less financially independent.3 What do we learn about the age-group of 18 to 29 in the U.S.? ______I.Young women are fast catching up with young men financiaily.J.Young men are more vulnerable to bankruptcy than young women.K.The past decade witnessed a dramatic financial change among them.L.About 45% of them have got financial support from their friends.4 What do young Americans say about the financial assistance they received from their parents? ______M.Most of them say it was used to cover unexpected expenses.N.More than half of them say it was for household expenses.O.Many say a great amount of it went toward entertainment.P.Some say a small share of it was about paying tuition or rent.5 What is said about the young adults nowadays in the U.S.? ______Q.The pace with which they reach markers of adulthood is speeding up.R.An increasing percent of them would like to live separately from their parents.S.They tend to spend more years in schooling and delay their marriage age.T.They are more likely to be financially independent after getting married.

In order to process your returns, we are required to check both the condition of the goods and the integrity of your reason for returning them. After checking and approving your returns, we will promptly reimburse (赔付) the purchase price of the returned items. Reimbursements are made to the payment method used at the time of purchase.If you have received a faulty product or a wrong item and you inform us of the mistake and return the items within 14 days of receipt, we will refund you the costs in full, including all charges for postage.If goods are returned after the expiration (截止日期) of the 14 day revocation period (退货期), you carry the cost of returning the goods. This will be deducted from the amount we refund you for the returned items. Please understand that we cannot refund any shipping fees in this case.Reimbursement is normally processed within 14 days of receipt of returned goods. However, we ask for your understanding if the processing time during peak periods should take longer.Please note that your bank may take up to 10 working days to process your refund. This depends on the institution from which a payment card is issued and the respective processing time.36. What will be checked about your goods in order to process your returns?A) Their price.B) Their condition.C) Their shipping fees.D) Their manufacturers.37. How will the refund be paid for the returned items?A) Usually by credit card.B) By a mobile payment method.C) In most cases through an online payment.D) By the same method used at the time of purchase.38. You can get your refund in full only if you ________.A) buy the items within this countryB) agree to carry the cost of returningC) return the items within 14 days of receiptD) have a contract with the seller in advance39. During peak periods, the processing of your reimbursement may take ________.A) two daysB) ten daysC) no more than a weekD) longer than 14 days40. The word "deducted" in Paragraph 3 means ________.A) kept outB) turned onC) taken awayD) broken down

No sooner had he arrived in Rome___ he heard of the good news.A. untilB. thenC. thanD. when

Why is table tennis played by so many people?A. It can be played in any place like retirement homes.B. It is a great way to improve ear-hand coordination.C. It can be played by people of all ages and physical abilities.D. It is the greatest athletic sport.

Dear Mr. Smith, I am writing to apply for the programmer position advertised in Jobs Now. As requested, I am now enclosing a completed job application, my résumé and three references. The role is very attractive to me, and I believe that my strong technical experience and education make me the best person for this position. My key strengths that would support my success in this position include: *I have successfully designed, developed and supported many software projects. *I always work hard for excellence(优秀). With a diploma in Computer Programming, I have a thorough understanding of the full lifecycle (生命周期) for software development projects. I am also capable of learning and applying new technologies. Please see my résumé for additional information on my experiences. I can be reached anytime by phone at 123-445-6767. Thank you for your time and consideration. I look forward to hearing from you soon. Sincerely, John DoeApplicant's Information Name: John Doe Position applied for: (48) Enclosure: a job application, a résumé and (49) Key strengths: 1)having designed, (50) many software projects. 2)always working hard for excellence Education: a (51) in Computer Programming Knowledge and skills: 1)understanding the full lifecycle for software development projects 2)being capable of (52) new technologies Contact: Tel. 123-445-6767

ⅹ Translate the following sentences into Chinese.1. Three days later, Wuhan went into a lockdown, which lasted for 76 days.It was over, the whole city breathed a sigh of relief.2. His efforts paid off, and the teacher offered Zhong an indefinite stay in which he declined as he was eager to return home.Many a time he has stressed that doctors shall be the first to rush to the field against the disease.4. Though honorable, he always says he's just a doctor with a sense of duty. And for this, people call him "a doctor with a caring heart."

句子结构分析: Kate's uncle lives in a village.A. 主系表B. 主谓C. 主谓宾D. 主谓宾宾E. 主谓宾宾补

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热门问题

  • 拼写合适的单词补全句子 ( 答案不区分大小写 ; 单词提示中根小短线代表一个 字母 ) A va---- is a space that contains no air or other gas.

  • 选择合适的单词补全句子

  • 一、拼写合适的单词补全句子(答案不区分大小写;单词提示中一根小短线代表一个字母) If someone is __ob---__ , they are extremely fat.

  • The increase in international business and in foreign investment has created a need for executives with knowledge of foreign languages and skills in cross-cultural communication. Americans, however, have not been well trained in either area and, consequently, have not enjoyed the same level of success in negotiation in an international arena as have their foreign counterparts. Negotiating is the process of communicating back and forth for the purpose of reaching an agreement. It involves persuasion and compromise, but in order to participate in either one, the negotiators must understand the ways in which people are persuaded and how compromise is reached within the culture of the negotiation. In many international business negotiations abroad, Americans are perceived as wealthy and impersonal. It often appears to the foreign negotiator that the American represents a large multi-million-dollar corporation that can afford to pay the price without bargaining further. The American negotiator’s role becomes that of an impersonal supplier of information and cash. In studies of American negotiators abroad, several traits have been identified that may serve to confirm this stereotypical perception, while undermining the negotiator’s position. Two traits in particular that cause cross-cultural misunderstanding are directness and impatience on the part of the American negotiator. Furthermore, American negotiators often insist on realizing short-term goals. Foreign negotiators, on the other hand, may value the relationship established between negotiators and may be willing to invest time in it for long-term benefits. In order to solidify the relationship, they may opt for indirect interactions without regard for the time involved in getting to know the other negotiator. Clearly, perceptions and differences in values affect the outcomes of negotiations and the success of negotiators. For Americans to play a more effective role in international business negotiations, they must put forth more effort to improve cross-cultural understanding. [共5题](1)What kind of manager is needed in present international business and foreign investment? [本题2分]A. The man who represents a large multi-million-dollar corporation. B. The man with knowledge of foreign languages and skills in cross-cultural communication. C. The man who is wealthy and impersonal. D. The man who can negotiate with his foreign counterparts.

  • 拼写合适的单词补全句子 ( 答案不区分大小写 ; 单词提示中一根小短线代表一个字母 ) A seq----- of events or things is a number of events or things that come one after another in a particular order.

  • 拼写合适的单词补全句子 ( 答案不区分大小写 ; 单词提示中一根小短线代表一个 字母 ) If there is a bo-- in the economy, there is an increase in economic activity.

  • 6. The children will now play some pieces of music that they ______ themselves. A.were taught posed C.accomplished D.worked7. While she waited,she tried to ______ her mind with pleasant thoughts of the vacation. A.occupy pose C.think D.intensify8. In the film,the peaceful life of a monk ______ the violent life of a murderer. A.is compared with B.is compared to C.is contrasted to D.is contrasted with9. ______ to pay for an order is simplicity itself. A.Use plastic B.Using plastics C.Using plastic D.Used plastic10. Additional time is required for cooking or ______ homemade dishes. A.chill B.to chill C.chilled D.chilling

  • If you_________in a job for several years, you may be able to accumulate a lot of work experience and skills that would be beneficial to your future career development.A. have workedB. had workedC. have been workingD. had been working

  • 拼写合适的单词补全句子 ( 答案不区分大小写 ; 单词提示中一根小短线代表一个 字母 ) To enh ---- something means to improve its value, quality, or attractiveness.

  • question or statement.Hot pot is a traditional dish in China. It is believed to date back more than 1,000 years to the time of the Jin Dynasty. Hot pot's origins can be found in the dining practices of Mongolian horsemen who rode across the steppe and into northern China. Legend has it that the Mongols used their helmets as pots to simmer (炖) broth (汤底) over open fires, and cooked chunks of meat in the broth.Hot pot cooking seems to have spread to northern China during the Tang Dynasty. In the regional variations developed with different ingredients such as seafood. In the centuries that witnessed the growth of the Song Dynasty, hot pot moved — and changed — further south, with each successive region adapting it to their local ingredients and tastes.The ingredients in a hot pot vary a lot from region to region. Perhaps the most famous hot pot is the Chongqing or Sichuan hot pot. It features a dark red broth chock-full (塞满了的) of spices, chili peppers, and the uniquely mouth-numbing Sichuan peppers. In Beijing and elsewhere in the north, hot pot broth tends to be mild and, compared to its racy southern "cousins", a little light. In the northeast of China, a kind of local sauerkraut (酸菜) is used to add some tang (强烈的味道), making the broth a bit sour. People can choose a version of hot pot according to their taste.1 Hot pot is believed to date back more than 1,000 years to the time of _______.A. the Jin Dynasty B. the Tang DynastyC. the Song Dynasty D. the Yuan Dynasty

  • The coming of the railways in the 1830s ________ our society and economic life.A. transferredB. transformedC. transportedD. transmitted

  • 选择合适的单词补全句子。-|||-I __ in the city.-|||-live lives

  • ⅢComplete the following sentences with the given sentence structures-|||-get ready for.sa为························备-|||-e.g.Susan has to buy a lot of things to get ready for her trip.(苏珊不得不买很多东西为旅行做准备。)-|||-1 The boy got up early to __ (为上学做准备).-|||-2 I have a lot of work to do to __ (为明天做准备).

  • 拼写合适的单词补全句子(答案不区分大小写;单词提提示中一根小短线代表一个字母)Something that is inf- - - - - has no limit,end,or edge.

  • The Harry Potter series, written by J.K. Rowling, is perhaps the most popular set of novels of the modern era. With seven books and many successful films to its name, the series has gathered about 15 billion dollars in sales. How did the series become so popular? The reason can be broken down into several areas.The first book in the series was rejected 12 times before it was picked up by Bloomsbury—a small publisher in England. So receiving this contract was Rowling's first step to success. However, getting a book contract does not ensure the success of a book. The story was soon loved by children and adults alike. In light of this, Bloomsbury Publishing published a second version of the books with “adult” (less colorful and more boring) book covers. This made it easier for a full range of ages to enjoy the series.Another factor that worked like a charm was that the publisher and Rowling herself, through the books, conducted midnight releases, promotions, and pre-ordering more readers. Customers who feared that their local bookstore would run out of copies responded by pre-ordering over 700,000 copies before the July 8, 2000 release.What does the underlined word “releases” (Para. 3) mean?A. The activity that frees or expresses energy or emotion.B. The announcement about the book’s publishing information.C. The sales of books that is available only at midnight.

  • 拼写合适的单词补全句子(答案不区分大小写;单词提示中一根小短线代表一个字母) Someone or something that is so---- is very serious rather than cheerful or humorous.

  • 拼写合适的单词补全句子 ( 答案不区分大小写 ; 单词提示中一根小短线代表一个 字母 ) To aut _ _ _ _ _ a factory , office , or industrial process means to put in machines which can do the work instead of people.

  • These drugs are available over-the-counter without a(n)__________. ()A. infectionB. dosageC. prescription

  • Elder and weaker Mr. Mag paid_visits to his old friends.A. scarceB. rare()C. insufficientD. inadequate

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