单选题When we think about addiction to drugs or alcohol, we frequently focus on negative aspects, ignoring the pleasures that accompany drinking or drug-taking. (21) the essence of any serious addiction is a pursuit of pleasure, a search for a "high" that normal life does not (22) . It is only the inability to function (23) the addictive substance that is dismaying, the dependence of the organism upon a certain experience and a(n) (24) inability to function normally without it. Thus a person will take two or three (25) at the end of the day not merely for the pleasure drinking provides, but also because he "doesn't feel (26) " without them. (27) does not merely pursue a pleasurable experience and need to (28) it in order to function normally. He needs to repeat it again and again. Something about that particular experience makes life without it (29) complete. Other potentially pleasurable experiences axe no longer possible, (30) under the spell of the addictive experience, his life is peculiarly (31) . The addict craves an experience and yet he is never really satisfied. The organism may be (32) sated, but soon it begins to crave again. Finally a serious addiction is (33) a harmless pursuit of pleasure by its distinctly destructive elements. A heroin addict, for instance, leads a (34) life: his increasing need for heroin in increasing doses prevents him from Working, from maintaining relationships, from developing in human ways. (35) an alcoholic's life is narrowed and dehumanized by his dependence on alcohol.

单选题Most of the independent secondary schools ______.

单选题Jack: ______?Lora: I'm an engineer.Jack: Oh, are you?Lora: How about you?Jack: I work for a trading company.

单选题The piano in the other shop will be ______, but ______.

单选题The evolution of sex ratios has produced, in most plants and animals with separate sexes, approximately equal numbers of males and females. Why should this be so? Two main kinds of answers have been offered. One is couched in terms of advantage to population. It is argued that the sex ratio will evolve so as to maximize the number of meetings between individuals of the opposite sex. This is essentially a "group selection" argument. The other, and in my view correct, type of answer was first put forward by Fisher in 1930. This "genetic" argument starts from the assumption that genes can influence the relative numbers of male and female offspring produced by an individual carrying the genes. That sex ratio will be favored which maximizes the number of descendants an individual will have and hence the number of gene copies transmitted. Suppose that the population consisted mostly of females, then an individual who produced sons only would have more grandchildren. In contrast, if the population consisted mostly of males, it would pay to have daughters. If, however, the population consisted of equal numbers of males and females, sons and daughters would be equally valuable. Thus a one-to-one sex ratio is the only stable ratio; it is an "evolutionarily stable strategy." Although Fisher wrote before the mathematical theory of games had been developed, his theory incorporates the essential feature of a game that the best strategy to adopt depends on what others are doing. Since Fisher's time, it has been realized that genes can sometimes influence the chromosome or gamete in which they find themselves so that the gamete will be more likely to participate in fertilization. If such a gene occurs on a sex-determining (X or Y) chromosome, then highly aberrant sex ratios can occur. But more immediately relevant to game theory are the sex ratios in certain parasitic wasp species that have a large excess of females. In these species, fertilized eggs develop into females and unfertilized eggs into males. A female stores sperm and can determine the sex of each egg she lays by fertilizing it or leaving it unfertilized. By Fisher's argument, it should still pay a female to produce equal numbers of sons and daughters. Hamilton, noting that the eggs develop within their host—the larva of another insect—and that the newly emerged adult wasps mate immediately and disperse, offered a remarkably cogent analysis. Since only one female usually eggs in a given larva, it would pay her to produce one male only, because this one could fertilize all his sisters on emergence. Like Fisher, Hamilton looked for an evolutionarily stable strategy, but he went a step further in recognizing that he was looking for a strategy.

单选题It is usual to classify types of production as job production, batch production and flow production. In job production, products are supplied to the special requirements of a customer, and the whole project is undertaken as one operation which is completed before passing, on to the next. A good example of this kind of work is shipbuilding. In job production a single item is produced at a time, whereas in batch production a number of similar items are produced in order to meet a continuing sales demand Batch sizes vary, but the quantity which is produced amounts to more than immediate requirements, and the surplus production is stored. Finally, in flow production, the manufacture of a product proceeds from one operation to another at a planned rate of output. It is argued that the type of production method which is employed depends on the development of an individual company. That. is to say, many factories begin manufacturing on a job production basis and proceed, as the volume of production increases, to batch and flow production methods. This is not always the case, however, since the type of production is not necessarily determined by the product volume which is aimed at. In fact, in the car industry, tools are produced by jobbing methods, components are produced by batch methods, and the final product is assembled by flow methods. Flow production is associated with flow layouts, whereas job and batch production are associated with process layouts. In a process layout, machines of a similar type are grouped together in the same section of the factory, and work in progress is moved from one part of the factory to another. In a flow layout scheme, the manufacturing equipment is arranged in the same sequence as the operations performed on the product. Each of these operations must be capable of processing work at the rate required for assembly of the final product, and the output for each operation must be balanced in order to provide a smooth flow of work. There are advantages in both types of layout. In a process layout system there is more flexibility, and a greater specialization of machines and labour is possible, while in a flow layout system it is not necessary to maintain a high level of stocks or to demand great skill in the workforce.

单选题Long Conversation 1 Questions 9 to 11 are based on the conversation you have just heard. （）

单选题All visitors are requested to ______ with the regulations.

单选题Until recently most historians spoke very critically of the Industrial Revolution. They (31) that in the long run industrialization greatly raised the standard of living for the (32) man. But they insisted that its (33) results during the period from 1740 to 1840 were widespread poverty and misery for the (34) of the English population. (35) contrast, they saw in the preceding hundred years from 1640 to 1740, when England was still a (36) agricultural country, a period of great abundance and prosperity. This view, (37) is generally thought to be wrong. Specialists (38) history and economics, have (39) two things: that the period from 1640 to 1740 was (40) by great poverty, and that industrialization certainly did not worsen and may have actually improved the conditions for the majority of the populace.

单选题(There) are (thousand) of (different) types (of) roses.A. ThereB. thousandC. differentD. of

单选题Responsibility rests with government, which should ______ serious and transparent debate Between those of different opinion, and provide the public with the honest evidence they need and deserve.

单选题The brave man was greatly honoured when the organizer announced, "You ______ a medal!"

单选题The retired engineer plunked down $50,100 in cash for a midsize Mercedes as a present for his wife—a purchase______with money made in the stock the week before. A. paid off B. paid through C. paid out D. paid for

单选题None of the soldiers was allowed to open fire unless heavy loss was shown to be ______ inevitable.

单选题 乒乓球在我国被誉为“国球”，是全世界最流行的球类运动之一。乒乓球像一个社会符号，在中国人心中占有重要的地位。乒乓球运动集健身性、竞技性和娱乐性为一体，其独特的魅力影响着几代中国人。经常打乒乓球，不但能增强体质，而且能锻炼一个人的反应能力，是一项非常有益健康的运动。中国乒乓球队成立于1952年，迄今为止已在世界三大赛事(奥运会、世界乒乓球锦标赛和乒乓球世界杯)中获得了很多枚金牌，取得了举世闻名的成就。

单选题Nobody knows why there are so few women at the ______ of movies.

单选题In a small school on the South Side of Chicago, 40 children between the ages of five and six sit quietly learning in a classroom. In 27 of each of them is a computer running software called Reading Eggs. Some are reading a short story, others 28 sentences with words they are learning. As they complete each task they move through a cartoon map that shows how far they have 29 in reading and writing. Along the way they collect eggs which they can use to buy objects in the game, such as items to 30 their avatar's apartment. Now and then a child will be taken 31 for scheduled reading periods with one of the two monitoring teachers. The director says this sort of teaching, blending software with human 32 , helps her pupils learn faster. It also allows teachers at this school to spend more time teaching and less time 33 written work and leading pupils through dull drills of words and numbers. The idea that technology can revolutionize (彻底改变；使革命化) education is not new. In the 20th century almost every new 34 was supposed to have big implications for schools. In many classrooms, computers have been used to improve 35 and keep pupils engaged. But they did not transform learning in the way their boosters predicted. It is wise, therefore, to be skeptical about the claims made for the current wave of innovation. Yet there are also 36 to believe that a profound shift is occurring. A. intervention F. ways K. efficiency B. building G. furnish L. progressed C. aside H. front M. reasons D. invention I. build N. back E. method J. marking O. doing