单选题The Browns spent________holidays in the country last summer

单选题Pupil: I apologize for being late this morning. My alarm clock never went off. Teacher: ______.

单选题The forest from which Man takes his timber is the tallest and most impressive plant community of Earth. In terms of Man's brief life it appears permanent and unchanging, save for the seasonal growth and fall of the leaves, but to the forester it represents the climax of a long succession of events. No wooded landscape we see today has been forest for all time. Plants have minimum requirements of temperature and moisture and, in ages past, virtually every part of Earth's surface has at some time been either too dry or too cold for plants to survive. However, as soon as climatic conditions change in favour of plant life, a fascinating sequence of changes occurs, called a primary succession. First to colonize the barren land are the lowly lichens, surviving on bare rock. Slowly, the acids produced by these organisms crack the rock surface, plant debris accumulates, and mosses establish a shallow root-hold. Ferns may follow and, with short grasses and shrubs, gradually form a covering of plant life. Roots probe even deeper into the developing soil and eventually large shrubs give way to the first trees. These grow rapidly, cutting off sunlight from the smaller plants, and soon establish complete domination—closing their ranks and forming a climax community which may endure for thousands of years. Yet even this community is not everlasting. Fire may destroy it outright and settlers may cut it down to gain land for pasture or cultivation. If the land is then abandoned, a secondary succession will take over, developing much faster on the more hospitable soil. Shrubs and trees are among the early invaders, their seeds calmed by the wind, by birds and lodged in the coats of mammals. For as long as it stands and thrives, the forest is a vast machine storing energy and the many elements essential for life.

单选题The tree fell down ______ she had time to run away.

单选题Sarah: Hello. Im calling to rent an apartment you advertised.Manager: Yes. What kind of apartment are you interested in?Sarah: I m interested in a one-bedroom apartment. 56__________?Manager

单选题She could not Urestrain/U her curiosity to see what was in the box before her guests had left.

单选题Rejecting the urging of his physician father to study medicine, Hawking chose to ______ on math and theoretical physics.

单选题SLICE: CAKE

单选题People Use Technology More, Sleep LessPeople in Britain now spend more time watching TV, gaming, and using their mobile phones and computers than sleeping. A study __31__ that British people use techn

单选题 Computers and Humans The ideal companion machine—the computer—would not only look, feel, and sound friendly but would also behave in a pleasant manner. Its informal conversational style make interaction comfortable, and yet the machine would remain slightly unpredictable (不可预知的) and therefore very interesting. In its first encounter it might be somewhat hesitant, but as it came to know the user it would progress to a more relaxed and intimate style. The machine would not be a passive participant but would add its own suggestions, information, and opinions; it would sometimes take the initiative in developing or changing the topic and would have a personality of its own. Friendships are not made in a day, and the computer would be more acceptable as a friend if it imitated the gradual changes that occur when one person is getting to know another. At an appropriate time it might also express the kind of affection that stimulates attachment and intimacy. The whole process would be accomplished in a subtle way to avoid giving an impression of over-familiarity that would be likely to produce irritation (恼怒). After experiencing a wealth of powerful, well-timed friendship indicators, the user would be very likely to accept the computer as far more than a machine and might well come to regard it as a friend. An artificial relationship of this type would provide many of the benefits that people obtain from interpersonal friendships. The computer would participate in interesting conversation that could continue from previous discussions. It would have a familiarity with the user's life as revealed in earlier contact, and it would be understanding and good-humored. The computer's own personality would be lively and impressive, and it would develop in response to that of the user. With features such as these, the computer might indeed become a very attractive social partner.

单选题You didn"t take his advice. ______ his advice, you ______ such a mistake.

单选题There is no evidence ______ oil price will come down in the near future.

单选题Mike: ______ Lynn: I'd love to, but I have to work on my history assignment. A. Shall we ask a few friends over this weekend? B. Why not come over for dinner this Saturday? C. What do you think of mountain climbing? D. Will you please go to the movie with us?

单选题During the 1990s world oil production will approach geological estimates of maximum production ______ , even with rapidly increasing petroleum prices. A. capability B. quota C. potentiality D. capacity

单选题It's high time that something ______ to prohibit selling fake commodities.

单选题 A number of children with special educational needs are home educated when schools cannot meettheir needs.As a parent,you must make sure that your child receives a full-time education suitable to

单选题Mother Teresa became famous for her hard work with ______ poor.

单选题Do you enjoy listening to records

单选题In the ______ of the project not being a success, the investors stand to lose up to USD 30 million.