单选题The city is an important railroad ______ and industrial and convention center. A. communication B. network C. junction D. link

单选题Space is full of unseen hazards among which are cosmic rays.

单选题Peter will ______ as managing director when Bill retires.

单选题His dislike of the course may prove to be a ______ barrier he cannot overcome.

单选题The problem of pollution as well as several other issues is going to be discussed when the Congress is in ______ again next spring. (2005年清华大学考博试题)

单选题He is a (an) ______ and well-behaved child, but his parents worry about him for he talks too little.

单选题The author skillfully fuses these fragments into a______whole.(2013年10月中国科学院考博试题)

单选题Smoking is so harmful to personal health that it kills people each year ______ than automobile accidents.

单选题He stepped {{U}}gingerly{{/U}} into the ramshackle old house.

单选题Colleges in the (newly formed) United Sates, (in recovering), from the adverse effects of the American Revolution, inaugurated (a broad curriculum) (in response of) social demands.

单选题Nail polish is made from cellulose Ulacquer/U, and opaque nail polish can be made by adding titanium oxide.

单选题The concept of a loyal opposition—the ______ of modern democracy—rarely prevails and, much more frequently, opposition is equated with treason and ruthlessly suppressed. A. loop B. essence C. equivalent D. velocity

单选题English speakers pick up pitch in the right hemispheres of their brains, but speakers of certain other languages perceive it on the left as well. It all depends on what you want to learn from pitch, Donald Wong of the Indiana School of Medicine in Indianapolis told the meeting last week. Earlier studies have shown that when an English speaker hears pitch changes, the right prefrontal cortex leaps into action. This fits in with the idea that emotive nuances of language—which in English are often carried by the rise and fall of the voice—are perceived on the fight. But in "tonal" languages like Thai, Mandarin and Swedish, pitch not only carries emotional information, but can also alter the meaning of a word. Wong and his colleagues suspected that a speaker of tonal language would register pitch in .the left side of the brain—in particular Broca"s area, which processes the linguistic content of language. To test this, the team asked English speakers and Thai speakers to listen to 80 pairs of Thai words, and tracked the blood flow in their brains using positron emission tomography. The volunteers had to decide whether the two words sounded the same, either by consonant or by tone. In some eases, the words had no intelligible meaning. None of the words was emotionally charged, so even when Thai speakers could understand them, there was no fight-side activation. But sure enough the Thai speakers consistently lit up the left side of the brain, especially Broca"s area, while the English speakers did not. The researchers are now planning to repeat the experiment with Thai speakers using whole sentences, complete with emotional information. "Both hemispheres will be engaged." predicts Wong.

单选题The population in last area was growing rapidly. Needless to say, the housing problem there {{U}}cried out{{/U}} for immediate solution.

单选题After a few short but interminable seconds, U. S. Astronaut Neil Armstrong placed his foot firmly on the fine-grained surface of the moon. The time was 10: 56 pm, July 20,1969.

单选题The puritan army executed the king, abolished the House of Lords, got the House of Commons to ______ England a "commonwealth", or republic.

单选题 There are many benefits to using online distance learning environments. Online education is available any place, any time for global communities of learners based on shared interests. Online education with its group-based instruction and computer mediated communication provides an opportunity for new development and understanding in teaching and learning. Computer mediated communication encourages collaborative learning by not providing cues regarding appearance, race, gender, education, or social status, bestowing a sort of anonymity to participants. Distance also permits the expression of emotion (both positive and negative) and promotes discussion that normally would be inhibited. Yet, this same text-based positive aspect of online learning makes online education more cumbersome and therefore takes more time than face-to-face learning. In addition, the sheer bulk of messages can be overwhelming. The learner 0nly has the written text and no other non-verbal cues. This may confuse the learner and cause misunderstanding. Some students are not willing to take the time to go in and look up homework assignments and other online learning activities. ESL students shy away from online classes. They have expressed fear of having their work, viewed by others. In the road to dotcom in education, educators "have to slow down from their busy lives to be free to focus first on connecting with learners and connecting them to learning before they end up feeling like they are no longer using technology, but are being used by it". There is pressure to keep up with the times as well as "a cost-of-entry issue regarding technology in education. Without a certain level of technology services and learning options, many students will not consider attending a certain institution". Mark Milliron claims that "any technology has to prove that it will ultimately improve or expand learning". This will come about if educators "slow down, look around, and get on the road to dotcom—a place to thoughtfully engage and explore all aspects of technology, good, bad, or indifferent... A place with mindful focus on the people and passions that make life worth living". Should online learning be an issue of control or should students be convinced of its value as an authentic learning tool? Fear and a threatening environment don't enhance learning according to brain-based learning research. "How students feel about a learning situation determines the amount of attention they devote to it." "Positive emotions ensure that learning will be retained." It's very. important to discuss with students how they feel about technology and online learning so that they feel good about what they are doing. The process of implementing online distance learning is a slow and delicate one. Change will eventually come about but it will take time.