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2017年考研英語專項訓練題及答案
閱讀理解
篇一：
Although recent years have seen substantial reductions in noxious pollutants from individual motor vehicles, the number of such vehicles has been steadily increasing. Consequently, more than 100 cities in the United States still have levels of carbon monoxide, particulate matter, and ozone (generated by photochemical reactions with hydrocarbons from vehicle exhaust) that exceed legally established limits. There is a growing realization that the only effective way to achieve further reductions in vehicle emissions — short of a massive shift away from the private automobile — is to replace conventional diesel fuel and gasoline with cleaner-burning fuels such as compressed natural gas, liquefied petroleum gas, ethanol, or methanol.
All of these alternatives are carbon-based fuels whose molecules are smaller and simpler than those of gasoline. These molecules burn more cleanly than gasoline, in part because they have fewer, if any, carbon-carbon bonds and the hydrocarbons they do emit are less likely to generate ozone. The combustion of larger molecules, which have multiple carbon-carbon bonds involves a more complex series of reactions. These reactions increase the probability of incomplete combustion and are more likely to release uncombusted and photochemically active hydrocarbon compounds into the atmosphere. On the other hand, alternative fuels do have drawbacks. Compressed natural gas would require that vehicles have set of heavy fuel tanks — a serious liability in terms of performance and fuel efficiency — and liquefied petroleum gas faces fundamental limits on supply.
Ethanol and methanol, on the other hand, have important advantages over other carbon-based alternative fuels: they have higher energy content per volume and would require minimal changes in the existing network for distributing motor fuel. Ethanol is commonly used as a gasoline supplement, but it is currently about twice as expensive as methanol, the low cost of which is one of its attractive features. Methanol’s most attractive feature, however, is that it can reduce by about 90 percent the vehicle emissions that form ozone, the most serious urban air pollutant.
Like any alternative fuel, methanol has its critics. Yet much of the criticism is based on the use of “gasoline clone” vehicles that do not incorporate even the simplest design improvements that are made possible with the use of methanol. It is true, for example, that a given volume of methanol provides only about one-half of the energy that gasoline and diesel fuel do; other things being equal, the fuel tank would have to be somewhat larger and heavier. However, since methanol-fueled vehicles could be designed to be much more efficient than “gasoline clone” vehicles fueled with methanol they would need comparatively less fuel. Vehicles incorporating only the simplest of the engine improvements that methanol makes feasible would still contribute to an immediate lessening of urban air pollution.
1. The author of the text is primarily concerned with
[A] countering a flawed argument that dismisses a possible solution to a problem.
[B] reconciling contradictory points of view about the nature of a problem.
[C] identifying the strengths of possible solutions to a problem.
[D] discussing a problem and arguing in favor of one solution to it.
2. According to the text, incomplete combustion is more likely to occur with gasoline than with an alternative fuel because
[A] the combustion of gasoline releases photochemically active hydrocarbons.
[B] the combustion of gasoline embraces an intricate set of reactions.
[C] gasoline molecules have a simple molecular structure.
[D] gasoline is composed of small molecules.
3. The text suggests which of the following about air pollution?
[A] Further attempts to reduce emissions from gasoline-fueled vehicles will not help lower urban air-pollution levels.
[B] Attempts to reduce the pollutants that an individual gasoline-fueled vehicle emits have been largely unsuccessful.
[C] Few serious attempts have been made to reduce the amount of pollutants emitted by gasoline-fueled vehicles.
[D] Pollutants emitted by gasoline-fueled vehicles are not the most critical source of urban air pollution.
4. Which of the following most closely parallels the situation described in the first sentence of the text?
[A] Although a town reduces its public services in order to avoid a tax increase, the town’s tax rate exceeds that of other towns in the surrounding area.
[B] Although a state passes strict laws to limit the type of toxic material that can be disposed of in public landfills, illegal dumping continues to increase.
[C] Although a town’s citizens reduce their individual use of water, the town’s water supplies continue to dwindle because of a steady increase in the total populating of the town.
[D] Although a country attempts to increase the sale of domestic goods by adding a tax to the price of imported goods, the sale of imported goods within the country continues to increase.
5. It can be inferred that the author of the text most likely regards the criticism of methanol as
[A] flawed because of the assumptions on which it is based.
[B] inapplicable because of an inconsistency in the critics’ arguments.
[C] misguided because of its exclusively technological focus.
[D] inaccurate because it ignores consumers’ concerns.
[答案與考點解析]
1. 【答案】C
【考點解析】這是一道中心主旨題。本文的中心主旨句是首段的尾句。通過對首段尾句以及其它段落主題句的閱讀和理解，可以推導出本題的正確選項是C�？忌谄平獯祟愵}型時一定要首先抓住原文的中心主旨句以及各段的主題句。
2. 【答案】B
【考點解析】本題是一道指代詞題型。根據題干中的“incomplete combustion”可將本題的答案信息來源迅速確定在第二段的第四句，該句中的指代詞“these”暗示本題的具體答案信息來源應該在第二段的第三句。通過閱讀和理解第二段的第三句可推導出本題的正確選項是B。考生在解題時對指代詞一定要認真理解。
3. 【答案】A
【考點解析】本題是一道審題定位題型。通過題干中的“air pollution”可將本題的答案信息來源迅速確定在第一段，因為第一段首句中含有“noxious pollutants”，都在談污染的問題。通過閱讀和理解第一段，尤其是第一段尾句即全文的中心主旨句，可推導出本題的正確選項是A。這是一道比較難的題�？忌诮忸}時一定要具備審題定位能力，還要具備歸納和推導能力。
4. 【答案】C
【考點解析】這是一道類比題型，因為本題題干中含有“parallels”(與……相當，與……一樣)一詞。本題題干已將類比的參照對象確定在第一段的首句。通過仔細閱讀和理解第一段的首句，可推導出本題的正確選項是C，因為該選項涉及的增減關系的前提條件和原文一脈相承�？忌谄平膺@種題型時應對原文所表達的內容與關系有明確的認識和把握，不可以無根據地推導。
5. 【答案】A
【考點解析】這是一道細節推導題型。本題題干中的“the criticism of methanol”把本題的答案信息來源確定在第四段的第一、二句。通過閱讀和理解這兩句話，尤其是第二句話，就可推導出本題的正確選項A�？忌谄平獗绢}時一定要注意第二句話的第一個詞“Yet”在語意上所起的作用�？忌诮忸}時一定要重視啟承轉合詞的出現和功能。
[參考譯文]
近年來，盡管單個機動車輛排放的有毒污染物已大幅減少，但這些機動車輛的數量一直在持續增長，結果是，在美國有100多個城市的大氣中一氧化碳、灰塵和臭氧(由車輛尾氣中的碳氫化合物經光化反應產生)的含量已超出了法定的限度。人們愈來愈認識到，實現車輛廢氣進一步減少而又不必大規模減少私家轎車的唯一有效途徑是用清潔燃料來代替傳統的柴油和汽油燃料。這些清潔燃料包括壓縮天然氣、液化石油氣、乙醇和甲醇。
所有這些替代產品都是碳基燃料，不過它們的分子要比汽油的分子小且簡單。它們可以比汽油燃燒得更徹底，部分原因在于，即使它們含有碳—碳化學鍵，含量也較少，而且它們釋放的碳氫化合物也不大可能產生臭氧。那些具有多重碳——碳化學鍵的大分子在燃燒時包含了一系列復雜的反應。這些反應增大了不完全燃燒的可能，并且更容易釋放未燃燒的碳氫化合物，而這些化合物又對光化學反應很活躍。另一方面，這些替代燃料也有自己的缺點。壓縮天然氣可能需要車輛配備一個笨重的油箱，這對車輛性能和燃料效率又極為不利，并且液化石油氣還面臨著供應上的根本限制。
從另一方面來看，甲醇和乙醇與其它的碳基替代燃料相比有重要的益處：它們具有單位體積更高的能量含量，而且對現存的燃料銷售網絡只需很小地改變。乙醇通常作為汽油的替代品，但目前它比甲醇要貴兩倍，因此甲醇的低廉價格便成為引人注目的特點。然而，甲醇最吸引人的特點還在于它可以減少90%形成臭氧的廢氣，而臭氧又是城市中最嚴重的污染物。
和其它的替代燃料一樣，甲醇也遭到了非難。可大多數批評都建立在使用“汽油系列”的車輛不進行最簡單的設計改進以可能使用甲醇燃料的基礎上。例如，事實上一定體積的甲醇和同體積的汽油和柴油相比，只能提供相當于它們大約一半的能量。在其它因素相同的條件下，油箱可能要大一點和重一點，然而，由于甲醇燃料的車輛可以設計得比使用甲醇的“汽油系列”車輛還要高效，它們可能需要更少的燃料。同時，對發動機進行最簡單的改進便可使用甲醇的車輛，這將對城市大氣污染的迅速減輕做出貢獻。
篇二：
One of the simplest and best known kinds of crystal is the ionic salt, of which a typical example is sodium chloride, or ordinary table salt. The fundamental components of an ionic salt are ions: atoms or molecules that have become electrically charged by gaining or losing one more electrons. In forming sodium chloride, for example, sodium atoms give up an electron (thereby becoming positively charged) and chlorine atoms gain an electron (thereby becoming negatively charged). The ions are attracted to one another by their opposite charges, and they stack together compactly, like tightly packed spheres.
Recently, scientists at Michigan State University created a new kind of crystal called an electride. In electrides, the anions (negative ions) are completely replaced by electrons, which are trapped in naturally formed cavities within a framework of regularly stacked cations (positive ions). Electrides are the first examples of ionic salts in which all these anionic sites are occupied solely by electrons.
Unlike other types of anions, anionic electrons do not behave as if they were simple charged spheres. In particular, because of their low mass and their tendency to interact with one another over great distances, they cannot be “pinned down” to any one location. Instead, they wander close to and among the atoms lining the cavity and interact with electrons in nearby cavities, perhaps changing places with them.
The properties of an electride depend largely on the distance between the cavities that hold trapped electrons. When the trapped electrons are far apart, they do not interact strongly, and so behave somewhat like an array of isolated negative charges. When they are closer together, they begin to display properties associated with large ensembles of identical particles. When they are still closer, the ensemble properties dominate and the electrons “delocalize”: they are no longer tightly bound within individual cavities but are more or less free to pass through the spaces within the framework of positive ions.
By synthesizing electrides from a variety of materials, one can vary the geometry of the anionic cavities and their relation to the surrounding cations. The resulting properties may make it possible for electrides to become a basis for economically useful new materials and devices. For instance, because the electrons in some electrides are very weakly bound, these crystals could be effective as photosensitive detectors, in which an impinging photon liberates an electron, resulting in a small electric current. The same weak binding could also make electrides useful in solar energy converters and as cathodes in batteries. One obstacle is the tendency of electrides to decompose through reaction with air and water. Researchers are seeking ways to increase their stability.
1. The text is primarily concerned with discussing
[A] a way to isolate electrons.
[B] the characteristics of a new kind of crystal.
[C] the structure of an ionic salt.
[D] commercial uses for electrides.
2. In the first paragraph, the author is primarily concerned with
[A] introducing a variant on the standard atomic theory.
[B] describing how chlorine atoms can become negatively charged.
[C] describing some early research at Michigan State University.
[D] providing background for the technical discussion to follow.
3. According to the text, the defining characteristic of an electride is which of the following?
[A] Its positive are of particularly low mass.
[B] Its ions possess identical electrical charges.
[C] It contains a framework of regularly stacked ions.
[D] Its negative ions consist solely of electrons.
4. It can be inferred from the text that anions behaving as “simple charged spheres” (line 2, paragraph 3) could be expected to
[A] readily lose electrons and become positively charged.
[B] move freely in and out of their cavities.
[C] respond to photons by liberating electrons.
[D] remain fixed relative to their cations.
5. With which of the following statements regarding electrides would the author most likely agree?
[A] They have proven themselves to be of great commercial value.
[B] Their future commercial value is promising but uncertain.
[C] They are interesting but of no practical value.
[D] They have commercial value mainly in solar energy applications.
[答案與考點解析]
1. 【答案】B
【考點解析】本題是一道中心主旨題。本文的中心主旨句在第二段的第一句，如果抓住了這句話并且聯系每段的中心主旨句，就可得出本題的正確選項B。其實本文第二段就是在講一種新的晶體的與眾不同的“characteristics”(特點)�？忌诮忸}時一定要首先找出全文的中心主旨句，并與上下文聯系。
2. 【答案】D
【考點解析】這是一道段落關系題。從第二段到尾段是本文作者闡述其中心思想的段落。在展開中心思想之前，作者為中心思想的展開進行了鋪墊(講述一般晶體的特點)，從而為第二段到尾段的陳述(講述一種新晶體的特點)提供明確的對比�？忌诮忸}時一定要注意段落之間的關系。
3. 【答案】D
【考點解析】這是一道審題定位題。題干中沒有給出明確的審題定位信息。破解此題需要考生平時的閱讀積累，這是一道較難的題目。題干中所涉及的是“the defining characteristic of an electride”(電子晶體的特點)。在第二段作者第一次在文章中談到了“electride”，所以其特點也應該在第二段向讀者交待，故本題的答案信息來源應該在第二段。綜合第二段第二、三句的內容可推導出本題的正確選項D�？忌诮忸}時一定要具備出色的審題定位能力。
4. 【答案】D
【考點解析】本題是一道句間關系與反推題。題干中的信息以將本題的答案信息確定在第三段。根據第三段所陳述的內容進行反推可得出本題的正確選項D。在進行反推時一定要注意第一句中的“do not behave as if…”以及第二句中的“cannot be pinned down”所起的作用�？忌诮忸}時一定要具備反推即逆向推理的能力。
5. 【答案】B
【考點解析】這是一道審題定位題。本題的題干沒有提供任何審題定位的信息。但是善于閱讀的考生應該知道每篇文章尾段的重要性。在本題到來之前本文的尾段還沒有涉及任何一道題，故考生應該首先從尾段中尋找本題的答案信息。尾段的第二句第四句表明新的晶體在商業方面的可利用性;尾段的第五句表明這種新的晶體的不足之處。可見本題的正確選項應該是B�？忌诮忸}時一定要對文章結構以及出題點有所認識，最好對全文有整體的把握。
[參考譯文]
在各種最簡單和最常見的晶體中，離子鹽是其中一例，它典型的實例就是氯化鈉，或普通的食鹽。離子鹽的基本組成成份便是離子，也就是那些由于得到或失去一個或多個電子而帶有電荷的原子或分子。例如，在形成氯化鈉的過程中，鈉原子釋放一個電子(從而帶有正電荷)而氯電子得到一個電子(從而帶有負電荷)。這些離子由于帶有相反的電荷而相互吸引，它們緊密地堆砌在一起就象緊密擠壓在一起的球體。
最近，密西根州立大學的科學家們研制出一種新的被稱為電子晶體的晶體。在電子晶體中，陰離子(即帶負電荷的離子)全部被電子替代，這些電子被困在自然形成的空穴中，而空穴位于規則堆砌的陽離子(即帶正電荷的離子)的框架內。電子晶體是第一種陰離子空間全被電子占據的離子鹽。
和其它類型的陰離子不同，作為陰離子的電子不像那些簡單的帶電球體。特別地，由于它們的質量很小而且有與遠距離的離子進行相互作用的傾向，它們不會被固定在任何一個位置。相反，它們會到處游離，或者緊靠那些在空穴邊上的原子，或者在這些原子之間游離，并且還和附近空中的電子發生相互作用，甚至于可能與它們交換位置。
電子晶體的特征很大程度上依賴于空穴間的距離，而這些空穴便是容納被捕獲電子的地方。當這些被捕獲的電子相距很遠時，它們之間的相互作用不強，因而在某種程度上表現為一組相互孤立的負電荷。但當它們間的距離很近時，它們便表現出一些特征來，很像大量相同離子的集合。當它們間的距離更近時，群體集合屬性更占主導地位，而且電子也出現“離位”現象：它們不再被束縛于單個的空穴之上，而是或多或少地可以在正離子的構架之間穿越。
通過從不同的材料來合成電子晶體，科學家們可以改變陰離子空穴的幾何結構，以及改變它們同周圍陰離子之間的關系。這些隨之而來的特征使得電子晶體可能成為經濟實用的新材料和新設備的基礎。例如，由于在某些電子晶體中，電子結合得非常微弱，從而使得這些晶體可以有效地用作光敏探測器。在這種探測器中，一束光子可以釋放一個電子，從而形成一股小電流。這種結合微弱的特性同樣可使電子晶體對太陽能轉換器和電池的陰極很有用�？呻娮泳w的一個缺陷在于它易于與空氣和水發生反應而分解。目前，研究人員正設法尋找提高電子晶體穩定性的方法。
篇三：
Defenders of special protective labor legislation for women often maintain that eliminating such laws would destroy the fruits of a century-long struggle for the protection of women workers. Even a brief examination of the historic practice of courts and employers would show that the fruit of such laws has been bitter: they are, in practice, more of a curse than a blessing.
Sex-defined protective laws have often been based on stereotypical assumptions concerning women’s needs and abilities and employers have frequently used them as legal excuses for discriminating against women. After the Second World War, for example, businesses and government sought to persuade women to vacate jobs in factories, thus making room in the labor force for returning veterans. The revival or passage of state laws limiting the daily or weekly work hours of women conveniently accomplished this. Employers had only to declare that overtime hours were a necessary condition of employment or promotion in their factory, and women could be quite legally fired, refused jobs, or kept at low wage levels, all in the name of “protecting” their health. By validating such laws when they are challenged by lawsuits, the courts have colluded over the years in establishing different, less advantageous employment terms for women than for men, thus reducing women’s competitiveness on the job market. At the same time, even the most well-intentioned lawmakers, courts, and employers have often been blind to the real needs of women. The lawmakers and the courts continue to permit employers to offer employee health insurance plans that cover all known human medical disabilities except those relating to pregnancy and childbirth.
Finally, labor laws protecting only special groups are often ineffective at protecting the workers who are actually in the workplace. Some chemicals, for example, pose reproductive risks for women of childbearing years: manufacturers using the chemicals comply with laws protecting women against these hazards by refusing to hire them. Thus the sex-defined legislation protects the hypothetical female worker, but has no effect whatever on the safety of any actual employee. The health risks to male employees in such industries cannot be negligible, since chemicals toxic enough to cause birth defects in fetuses or sterility in women are presumably harmful to the human metabolism. Protective laws aimed at changing production materials or techniques in order to reduce such hazards would benefit all employees without discriminating against any.
In sum, protective labor laws for women are discriminatory and do not meet their intended purpose. Legislators should recognize that women are in the work force to stay and that their needs — good health care, a decent wage, and a safe workplace — are the needs of all workers. Laws that ignore these facts violate women’s rights for equal protection in employment.
1. According to the author, which of the following resulted from the passage or revival of state laws limiting the work hours of women workers?
[A] Women workers were compelled to leave their jobs in factories.
[B] Many employers had difficulty in providing jobs for returning veterans.
[C] Many employers found it hard to attract women workers.
[D] The health of most women factory workers improved.
2. The author places the word “protecting” in quotation marks in line 9, paragraph 2 most likely in order to suggest that
[A] she is quoting the actual wording of the laws in question.
[B] the protective nature of the laws in question should not be overlooked.
[C] protecting the health of workers is important to those who support protective labor laws.
[D] the laws in question were really used to the detriment of women workers, despite being overtly protective in intent.
3. The text suggests that which of the following is a shortcoming of protective labor laws that single out a particular group of workers for protection?
[A] Such laws are often too weak to be effective at protecting the group in question.
[B] Such laws are usually drafted by legislators who do not have the best interests of workers at heart.
[C] Such laws exert no pressure on employers to eliminate hazards in the workplace.
[D] Compliance with such laws is often costly for employers and provokes lawsuits by employees claiming discrimination.
4. According to the first paragraph of the text, the author considers which of the following to be most helpful in determining the value of special protective labor legislation for women?
[A] A comparative study of patterns of work-related illnesses in states that had such laws and in states that did not.
[B] An estimate of how many women workers are in favor of such laws.
[C] An analysis of the cost to employers of complying with such laws.
[D] A study of the actual effects that such laws have had in the past on women workers.
5. The author implies that which of the following is characteristic of many employee health insurance plans?
[A] They cover all the common medical conditions affecting men, but only some of those affecting women.
[B] They lack the special provisions for women workers that proposed special labor laws for women would provide.
[C] They pay the medical costs associated with pregnancy and childbirth only for the spouses of male employees, not for female employees.
[D] They meet minimum legal requirements, but do not adequately safeguard the health of either male or female employees.
[答案與考點解析]
1. 【答案】A
【考點解析】這是一道指代詞題型。考生可根據題干中的“the passage or revival of state laws limiting the work hours of women workers”將本題迅速定位在第二段的第三句，該句中的指代詞“this”暗示本題的正確答案應該在第二段的第二句。這樣就可以找出本題的正確答案A。考生在解題時一定要注意指代詞。
2. 【答案】D
【考點解析】本題是一道標點符號題。英語作為一種語文，標點符號是非常重要的。在原文中“protecting”一詞被打上引號，其含義是“所謂的保護”，作者所表達的真實含義是“沒有起到保護作用的保護”。由此可見本題的正確答案應該是D�？忌诮忸}時要重視標點符號，尤其是一些特殊的標點符號。
3. 【答案】C
【考點解析】本題是一道歸納推導題型�？忌筛鶕}干中的“protective labor laws that single out a particular group of workers for protection”將本題的答案信息迅速確定在第三段的第一句，從第三段的內容(尤其是第三段的首尾兩句)判斷本題的正確答案應該是C�？忌诮忸}時首先要具備審題定位的能力，然后要善于歸納和總結段落的細節信息。
4. 【答案】D
【考點解析】這是一道細節推導題。本題的題干以將本題的答案信息來源確定在第一段，第一段的第二句是本題正確答案D的準確信息來源也是全文的中心主旨句�？忌诮忸}時一定要時時牢記全文的中心主旨句，尤其是在迷失解題思路時。
5. 【答案】A
【考點解析】這是一道細節推導題。根據本題題干中的“employee health insurance plans”可將本題的答案信息來源迅速確定在第二段的尾句，從第二段尾句的內容可判斷本題的正確答案應該是A�？忌诮忸}時一定要把審題定位放在第一位。
[參考譯文]
婦女勞動特別保護法的辯護者經常堅持認為，廢除這種法律就會破壞一個世紀以來為保護婦女工人而斗爭的成果。但是，只要對法庭案例和雇主的歷史作短暫回顧，就能夠發現這些法律的成果是多么的令人不愉快：實際上，這種法律與其說是一件好事，不如說是一種災禍。
以性別為界限的保護性法律通常是根據有關婦女的需要和能力的陳腐性假想為基礎的，而且雇主也經常使用這些法律作為他們歧視婦女的合法借口。例如，第二次世界大戰之后，企業和政府都企圖說服婦女離開她們的工廠中的工作，從而為回國的老兵們在勞動力市場中空出位子�；謴突蛲ㄟ^限制婦女每天或每周工作時間的州法律，很容易地就實現了上述的目標。雇主只需聲稱超時加班是在他們的工廠進行工作或提升的必要條件，這樣婦女就被合法地解雇，被拒絕給予工作或者保持一種較低的工資水平，所有這些都以“保護”婦女健康的名義得以實現。當受到法律訴訟時，法庭在過去數年中一直與雇主合謀共同建立一種男女不同的，對婦女更為不利的雇傭條件，從而降低了婦女在就業市場上的競爭力。同時，即使那些最善意的立法者、法庭和雇主也經常對婦女的真實需求視而不見。法律制定者和法庭都繼續允許雇主向雇員提供這樣的健康保險計劃，它包含了所有已知的人類疾病，但卻未包括那些與懷孕和生育相關的醫療內容。
最后，那些只保護特殊群體的勞動法在保護實際工作中的工人方面經常是無效的。例如，某些化學物質會對懷孕期間的婦女造成生育上的危險。使用這些化學物品的制造商們就會遵守保護婦女避免這些危險的法律而拒絕雇傭她們。因此這種特別界定的法律保護了假設中的婦女工人，但對工人實際的任何安全問題都沒有作用。在這些工廠中，對男性工人健康的危險也不能被忽略，既然那些化學毒素能導致胎兒的生育缺陷或使婦女不育，那么推而廣之，其必然會對人類的新陳代謝有害。目的在于減少這種危險的保護性法律，會改變生產原料或生產技術，從而給所有雇員帶來好處，而又不歧視任何一類雇員。
總而言之，為婦女制定的勞動保護法是帶有歧視性的，而且并沒達到它們預期的目的。立法者應該認識到，婦女是勞動力的一部分，而且她們的需求(如良好的健康保健，體面的工資收入，以及安全的工作環境)同時也是所有工人的需求。那些忽略這些事實的法律就會破壞婦女在就業中享受平等保護的權利。