Are there any differences between you and your sister? -- （）.

The publishing business is no___(differ)from any other business in this respect.

The law of country doesn’t ____ against any one.

A、discriminate

B、differ

C、contrast

D、distinguish

A.all tuples in a relation must be distinct(独一无二的)

B.every relation has a key(键)

C.all of the above

D.for any two tuples,the values associated with one or more of thei rattributes(属性)must differ

By almost any measure , there is a boom in Internet-based instruction . In just a few years , 34 percent of American universities have begun offering some form of distance learning (DL), and among the larger schools , it’s closer to 90 percent . If you doubt the popularity of the trend, you probably haven’t. It enrolls 90,000 student, a statistic used to support its claim to be the largest private university in the country.

While the kinds of instruction offered in these programs will differ, DL usually signifies a course in which the instructions post syllabi(课程大纲), reading assignments , and schedules on Websites , and students send in their assignments by e-mail . Generally speaking, face-to-face communication with an instructor is minimized or eliminated altogether.

According to the passage , distance learning is basically characterized by_____

A) A considerable flexibility in its academic requirements

B) The great diversity of students’ academic backgrounds

C) A minimum or total absence of face-to-face instruction

D) t the casual relationship between students and professors

By almost any measure , there is a boom in Internet-based instruction . In just a few years , 34 percent of American universities have begun offering some form of distance learning (DL), and among the larger schools , it’s closer to 90 percent . If you doubt the popularity of the trend, you probably haven’t. It enrolls 90,000 student, a statistic used to support its claim to be the largest private university in the country.

While the kinds of instruction offered in these programs will differ, DL usually signifies a course in which the instructions post syllabi(课程大纲), reading assignments , and schedules on Websites , and students send in their assignments by e-mail . Generally speaking, face-to-face communication with an instructor is minimized or eliminated altogether.

What accounts for the high drop-out rates for online students？

A) There is no strict control over the academic standards of the courses.

B) The evaluation system used by online universities is inherently weak.

C) There is no mechanism to ensure that they make the required effort.

D) Lack of classroom interaction reduces the effectiveness of instruction.

anking them according to an overall numerical score that is a composite of ratings according to several criteria. However, the overall scores generally should not be used by students as the basis for deciding to which colleges to apply. Which of the following, if true, most helps to justify the counselor s recommendation？

A．The vast majority of people who purchase the magazine in which the list appears are not college-bound students.

B．Colleges that are ranked highest in the magazine"s list use this fact in advertisements aimed at attracting students.

C．The rankings seldom change from one year to the next.

D．The significance that particular criteria have for any two students is likely to differ according to the students" differing needs.

E．Some college students who are pleased with their schools considered the magazine"s rankings before deciding which college to attend.

By almost any measure , there is a boom in Internet-based instruction . In just a few years , 34 percent of American universities have begun offering some form of distance learning (DL), and among the larger schools , it’s closer to 90 percent . If you doubt the popularity of the trend, you probably haven’t. It enrolls 90,000 student, a statistic used to support its claim to be the largest private university in the country.

While the kinds of instruction offered in these programs will differ, DL usually signifies a course in which the instructions post syllabi(课程大纲), reading assignments , and schedules on Websites , and students send in their assignments by e-mail . Generally speaking, face-to-face communication with an instructor is minimized or eliminated altogether.

Many students take Internet -based courses mainly because they can_____

A) Earn their academic degrees with much less effort

B) Save a great deal on traveling and boarding expenses

C) Select courses from various colleges and universities

D) Work on the required courses whenever and wherever

s laugh and smile, only human beings. So does laughter help us to survive in any way？ The answer seems to be that smiling and laughter help us to relax, reducing tension and preventing illnesses which are caused by stress. Laughter really is the best medicine!

But if you're unhappy, it can't do you any good to smile, can it？ Not true. Apparently, the positive effects of smiling are just the same whether you feel like smiling or not. Scientists in California asked a group of actors to act five different feelings; happiness, sadness, anger, surprise and fear—just using their faces. Changes in their heart rate, blood pressure and temperature were written down. Most of the feelings they acted didn't cause changes, but when the actors smiled, their heart rate and their blood pressure went down. This happened to make them feel better.

A sense of humor also helps to keep things in perspective. Interfering friends or a flat tire won't seem quite so bad if you can see the funny side. So if you find yourself in a stressful situation, try to imagine how it must seem to an outsider with a sense of humor and let yourself laugh. A psychologist writes, " If people try to show a positive reaction instead of a negative one, this will eventually become part of their personality. If you start to laugh, in time you will actually become happier.

How do people differ from other animals？

Software entities are more complex for their size than perhaps any other human construct, because no two parts are alike (at least above the statement level). If they are, we make the two similar parts into one, a （）, open or closed.In this respect software systems differ profoundly from computers, buildings, or automobiles, where repeated elements abound. Digital computers are themselves more complex than most things people build; they have very large numbers of states.This makes conceiving, describing, and testing them hard.Software systems have orders of magnitude more（）than computers do. Likewise, a scaling-up of a software entity is not merely a repetition of the same elements in larger size; it is necessarily an increase in the number of different elements.In most cases, the elements interact with each other in some（）fashion, and the complexity of the whole increases much more than linearly. The complexity of software is a(an) （）property, not an accidental one.Hence descriptions of a software entity that abstract away its complexity often abstract away its essence.Mathematics and the physical sciences made great strides for three centuries by constructing simplified models of complex phenomena, deriving, properties from the models,and verifying those properties experimentally.This worked because the complexities（）in the models were not the essential properties of the phenomena.It does not work when the complexities are the essence. Many of the classical problems of developing software products derive from this essential complexity and its nonlinear increases with size.Not only technical problems but management problems as well come from the complexity.

A.task B.job C.subroutine D.programA.states B.parts C.conditions D.expressionsA.linear B.nonlinear C.parallel D.additiveA.surface B.outside C.exterior D.essentialA.fixed B.included C.ignored D.stabilized

根据以下内容回答题：

Expectations for personal relationships differ greatly across cultures．It is important to know that most AmericanS value close friendships，they also value privacy and independence．From an American perspective，to have privacy or to give someone privacy is considered posi-tive．Yet。when the word“privacy”is translated into other languages（e．g．Russian，Arabic，and Japanese）．it has more of a negative meaning．（In these languages“privacy”means aloneness or loneliness．）Therefore，the American’s need for privacy is sometimes judged negatively by those who have not been raised with the value of individualism．some Americans are isolated from others because they have taken their independence and privacy to an extreme．Others simply like spending time alone or at least having the freedom to avoid socializing if they choose． In any true friendship，whatever the culture may be， a person is expected to show interest and concen in a friend’S serious problems．But how does one show this across cuhures？It is not possible to generalize about Americans because there are SO manv varieties of Americans．but it is possible to say that many foreigners or newcomers from different cultures have felt disappointed by Americans．A common occurrence is when an American does not Dhone or visit as much．as the foreigner expects．If someone from another culture is having a serious problem，Americans may say，“Let me know if there’s anything l．can do to help．”If the Americans do not receive．a specific request，they may feel that there’s nothing they can do．In this case．They may call every now and then to stay in touch．The friend from a different culture，on the other hand，may be expecting“sympathy calls or frequent visits，and may not hesitate to demon．strate a dependence on a friend．Many Americans arc uncomfortable whrn people become too dependent．

What do Americans lay emphasis on concerning expectations for personal relationships？

A.Close friendships．

B.Privacy．

C.Valuable culture．

D.Both A and B．