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1、2022年考博英语-黑龙江大学考前模拟强化练习题（附答案详解）1. 单选题Even today, a century after Pasteur developed the first vaccine, rabies almost always kills （ ）in the earliest stages of the disease.问题1选项A.its victims unless inoculatedB.the victims unless there is an inoculationC.the victims unless inoculatedD.its victims unles
2、s they are inoculated【答案】B【解析】考查语法结构。unless后面接条件状语从句，首先排除A、C项，句意要表达的是如果受害者能接种疫苗，而不是狂犬病被接种疫苗。句意：即使在今天，巴斯德开发出第一种疫苗后的一个世纪，狂犬病几乎总能杀死受害者，除非在疾病的早期阶段接种疫苗。故B项正确。2. 单选题Every possible means（ ）tried, but there is no result.问题1选项A.have beenB.has beenC.will beD.were【答案】B【解析】考查语法。主语为“every possible means”为单数，故谓语动
3、词用单数。而且means与try之间为被动关系，故B项正确。句意：所有可行的办法都尝试了，但仍然没有用。3. 写作题Directions: Nowadays, traffic problem remains one of the most serious situations in urban areas. Write an essay of 180-200 words to discuss this topic. Your essay must include the instructions as follows:1. Present situations2. Possible reaso
4、ns3. What should be done to solve this problem【答案】略4. 单选题（ ）tomorrow, he would get there by Friday.问题1选项A.Would he leaveB.Was he leavingC.If he leavesD.Were he to leave【答案】D【解析】考查虚拟语气。由tomorrow可知，从句表示的是对将来事实的虚拟，从句谓语动词的形式有三种，即were to do, should do, 动词的过去式（be动词用were）。并且可将if去掉，将谓语动词放于主语前。故D项正确。句意：如果他明天
5、出发，他周五将到达那里。5. 不定项选择题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 m
6、ore 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 changed). The ions are attracted to one another by their opposite charges, and they stack together compactl
7、y, 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 c
8、ations (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
9、 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
10、 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
11、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
12、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 elect
13、rides 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
14、obstacle is the tendency of electrides to decompose through reaction with air and water. Researchers are seeking ways to increase their stability.1. The passage is primarily concerned with discussing _.2. In the first paragraph, the author is primarily concerned with _.3. It can be inferred from the
15、 passage that the differences between the behavior of anionic electrons and normal anions result from which of the following features of electrons, as compared to normal anions?I. The much lower mass of electrons.II. The much greater tendency of electrons to interact with one another over large dist
16、ances.III. The much greater likelihood of electrons to remain trapped in naturally formed anionic cavities.4. According to the passage, the defining characteristic of an electride is which of the following?5. It can be inferred from the passage that anions behaving as “simple charged spheres” (3rd paragraph)
