【正文】 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 heard of the University of Phoenix. It grants degrees entirely on the basis of online instruction. It enrolls 90,000 students, 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 instructors post syllabi , reading assignments, and schedules on Websites, and students send in their assignments by . Generally speaking, facetoface munication with an instructor is minimized or eliminated altogether.The attraction for students might at first seem obvious. Primarily, there’s the convenience promised by courses on the Net: you can do the work, as they say, in your pajamas . But figures indicate that the reduced effort results in a reduced mitment to the course. While dropout rates for all freshmen at American universities is around 20 percent, the rate for online students is 35 percent. Students themselves seem to understand the weaknesses inherent in the setup. In a survey conducted for eCornell, the DL division of Cornell University, less than a third of the respondents expected the quality of the online course to be as good as the classroom course.Clearly, from the schools’ perspective, there’s a lot of money to be saved. Although some of the more ambitious programs require new investments in severs and networks to support collaborative software, most DL courses can run on existing or minimally upgraded systems. The more students who enroll in a course but don’t e to campus, the more the schools saves on keeping the lights on in the classrooms, paying doorkeepers, and maintaining parking lots. And, while there’s evidence that instructors must work harder to run a DL course for a variety of reasons, they won’t be paid any more, and might well be paid less.( )51. What is the most striking feature of the University of Phoenix?A. All its courses are offered online. B .Its online courses are of the best quality.C. It boasts the largest number of students on campus.D. Anyone taking its online courses is sure to get a degree.( )52 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 backgroundsC. a minimum or total absence of facetoface instructionD . the casual relationship between students and professors( )53. Many students take Internetbased courses mainly because they can ________. A. earn their academic degrees with much less effort B. save a great deal on traveling and boarding expenseC. select courses from various colleges and universitiesD. work on the required courses whenever and wherever( )54. What accounts for the high dropout 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.( )55. According to the passage, universities show great enthusiasm for DL programs for the purpose of ________.kind of gray cloud.39。s need 9 to 10 hours. Many live in a state of chronic sleep deficit that can affect mood, behavior, schoolwork and reaction time. Dr. Mary Carskadon, a sleep researcher at Brown University, describes sleepdeprived teenagers as existing in a 39。39。39。t open and a powerful instinct to curl up under something warm. Is this the same person who swore he wasn39。 A The case for college has been accepted without question for more than one generation. All high school graduates ought to go, says conventional wisdom and statistical evidence, because college will help them earn money, bee “better” people, and learn to be more responsible citizens than those who don’t go.But college has never been able to work its magic for everyone. And now that close to half our high school graduates are attending, those who don’t fit the patter