单选题______if I had arrived yesterday without letting you know beforehand?

单选题The case of Schutt helmet demonstrated that ______.

单选题Speaker A: I'm not at all satisfied with the service.Speaker B:______A. Nobody has complained like that before.B. I sincerely apologize for that.C. I wonder why you are satisfied with it.D. It' s not our fault as there are too many customers.

单选题The accommodation was at a comfortable hotel, the meeting facilities ______.

单选题He also acknowledges that, in general, state-owned companies do have an advantage _______the stability, management and career prospects they offer.

单选题The ice is too thin to______your weight.

单选题They put some money away each month ______ rainy days. A. in favor of B. in need of C. for the sake of D. at the risk of

单选题If we don't stop flirting with those deathly nuclear weapons, the whole globe will be ______. A. empowered B. punished C. polluted D. annihilated

单选题Video games have become increasingly realistic, especially those involving armed combat. America's armed forces have even used video games (1) recruitment and (2) tools. But the desire to play games is not the (3) why the United States Air Force recently (4) a procurement request for 2,200 Sony PlayStation 3 (PS3) video-game consoles. It intends to link them (5) to build a supercomputer that will (6) Linux, a free, open-source operating system. It will be used for research, including the development of high-definition imaging systems for radar, and will cost around one-tenth as much as a conventional supercomputer. The air force has already built a smaller computer (7) a cluster of 336 PS3s. This is merely the latest example of a(n) (8) trend. There is a long tradition of technology developed for military use filtering (9) to consumer markets: satellite-navigation systems (10) to guide missiles can also help hikers find their way, and head-up displays have (11) from jet fighters to family cars. But technology is increasingly moving in the other (12) , too, as consumer products are (13) for military use. Traditionally the military has preferred to develop and control its own technology, not just for tactical advantage but also to (14) that equipment was tough and (15) enough for those whose lives would depend on it. That began to change after the cold war as defence budgets became (16) and the development of (17) industrial and consumer products accelerated. As some of these technologies have become commoditized products which are (18) to everyone—friend and foe alike—there seems less (19) not to buy them and use the savings for more critical equipment that needs to be built-to-order. And consumer products can often be tweaked to make them more rugged or (20) when necessary.

单选题The scientific community was ______ when a living specimen of the coelacanth, long thought to be ______ was discovered by deep-sea fisherman. A. perplexed... common B. overjoyed... dangerous C. unconcerned... local D. astounded... extinct

单选题Some people viewed the findings with caution, noting that a cause-and-effect relationship between passive smoking and cancer remains______ . A．to be shown B．to have shown C．to have been shown D．being shown

单选题Although the study of genetics is an entirely new field, it______mankind for many years.

单选题What is an Advance Directive?

单选题In the opinion of the writer, why do women still earn less money than men?

单选题Papusek noticed in his studies that baby ______. A. would make learned responses when it saw the milk B. would carry out learned movements when it had enough to drink C. would continue the simple movements without being given milk D. would turn its head to right .or left when it had enough to drink

单选题The head of the navy heaped scorn on both the methods and motives of the conspirators.

单选题A: Here"s a gift for you, I bought it in India. B: ______