题目

下列化学用语既能表示一种元素，又能表示一个原子，还能表示一种物质的是A. O B. Fe C. N2 D. CO 答案：【答案】B【解析】A、O属于气态非金属元素，可表示氧元素，表示一个氧原子，但不能表示一种物质，不符合题意；B、Fe属于金属元素，可表示铁元素，表示一个铁原子，还能表示铁这一物质，符合题意；C、该符号是氮气的化学式，表示氮气这种物质和一个氮气分子，不能表示一种元素，不符合题意；2、No matter how long your life is, you will, at best, be able to read only a few books of all that have been written, and the few you do read should include the best. It is to be expected that the selections will change over time. Yet there is a surprising uniformity （一致） in the lists which represent the best choices of any period.     What are the signs by which we may recognize a great book? The four I will mention may not be all there are, but they are the ones I’ve found most useful in explaining my choices over the years.     Great books are probably the most widely read. They are not best sellers for a year or two. They are enduring best sellers. Gone with the Wind has had relatively few readers compared to the plays of Shakespeare or Don Quixote. It would be reasonable to estimate that Homer Iliad has been read by at least 25,000,000 people in the last 3000 years.     Great books are popular, not pedantic. They are not written by specialists about specialties for specialists. Whether they are philosophy or science, or history or poetry, they treat of human, not academic problems. They are written for men, not professors. To read a textbook for advanced students, you have to read an elementary textbook first. But the great books can be considered elementary in the sense that they treat the elements of any subject matter. They are not related to one another as a series of textbooks, graded in difficulty or in the technicality of the problems with which they deal. Great books are always contemporary, the most readable and instructive. Great books deal with the persistently unsolved problems of human life. There are genuine mysteries in the world that mark the limits of human knowing and thinking. Great minds acknowledge mysteries honestly. Wisdom is fortified （加强）, not destroyed, by understanding its limitations. 1．Which is NOT the criterion in the following when evaluating a great book?        A．Although not a best seller, it must be the most widely read.        B．A great book can be read without any effort.        C．Great books are never out of date.        D．Great books will not disappoint you if you try to read them well. 2．According to the author, Gone With the Wind is ______.        A．a best seller                B．disgusted by readers who like Shakespeare        C．read more often than Don Quixote        D．a great book 3．After reading the passage, we can infer that ______.    A．different periods have different lists of best books because there are many books for       people to choose from    B．if you don’t read an elementary textbook, you may have difficulty in understanding an       advanced one    C．Homer Iliad must be a best seller when it came out    D．great books often deal with unsolved problems of human life for the writers have       confidence in settling them 4．The best title for this passage is ______.        A．Great Books in Your Life                      B．Great Books in Your Specialty C．How to Find a Great Book?          D．What Is a Great Book?