单选题With______audiences and less financial support from government, Britain's best orchestras must find new sources of income, if they are to continue.

单选题If you explained the situation to your solicitor, he ______ able to advise you much better than I can. A. would be B. will have been C. was D. were

单选题During the Roman Republic around 50 BC, to protect the grain trade, heavy fines were imposed on anyone directly, deliberately, they insidiously stopped supply ships.

单选题Although ancient tools were ______ preserved, enough have survived to allow us to demonstrate an occasionally interrupted but generally ______ progress through prehistory.

单选题This disease ______ itself in yellowness of the skin and eyes. A. manifests B. modifies C. magnifies D. exposes

单选题The pair go shopping together, eat out and have recently______at a celebrity function.

单选题Fog is common near ______ inland bodies of water and along coasts in temperate zones.

单选题Theoretically, lending rates have already been liberalized, with no floor on them; in reality, bankers say they still price loans off the______.

单选题We can make an exception ______.

单选题We hold these truths to be self-______: that all men are created equal.

单选题I went there in 1984, and that was the only occasion when I ______ the journey in exactly two days. A. must take B. must have made C. was able to make D. could make

单选题Scholars come to the agreement that the Malthusian catastrophe has already occurred in isolated cultures that had no means of ______ resources.

单选题The following are all correct responses to "Who told the news to the teacher?" EXCEPT______.

单选题Most of us are neither pilots nor astronauts. We are not trained to steer large hulks of steel and gasoline while manipulating small computers. So there's something blindingly obvious about the risks of texting while driving. Yet research is beginning to show that driving while simply talking on a cell phone — including using hands-free technology — can prove dangerous, even deadly. In late July, the Center for Auto Safety released hundreds of pages of a study that identified the cell phone as a serious safety hazard when used on the road. And though it's impossible to accurately calculate how many car accidents nationwide are cell phone related, David Strayer, a psychology professor at the University of Utah, estimates that only 2% of people are able to safely multitask while driving. Strayer, who for more than a decade has been studying the effects driving and cell-phone use have on the brain, says those 2% are probably the same people who would be really good fighter pilots. Rarities. Some of Strayer's other findings show that most drivers tend to stare straight ahead while using a cell phone and are less influenced by peripheral vision. In other words, "cell phones," he says, "make you blind to your own bad driving." And even though the common assumption is that hands-free technology has reduced the more dangerous side effects of cell-phone use, a series of tests conducted by Strayer seems to indicate the opposite. A passenger acted as another set of eyes for the driver in the test and even stopped or started talking depending on the difficulty of conditions outside the car. Meanwhile, half the drivers talking on a hands-free phone failed, bypassing the rest area the test had called for them to stop at. Part of the problem may be that when people direct their attention to sound, the visual capacity of their brain decreases, says Steven Yantis, a professor of psychological and brain sciences at Johns Hopkins University. It can be as if a driver is seeing the image in her head of the person she is talking to, thereby decreasing her ability to see what's actually in front of her.

单选题Human vision, like that of other primates, has evolved in an arboreal environment. In the dense, complex world of a tropical forest, it is more important to see well than to develop an acute sense of smell. In the course of evolution, members of the primate line have acquired large eyes while the snout has shrunk to give the eye an unimpeded view. Of mammals, only humans and some primates enjoy color vision. The red flag is black to the bull. Horses live in a monochrome world. Light visible to human eyes, however, occupies only a very narrow band in the whole electromagnetic spectrum. Ultraviolet rays are invisible to humans, though ants and honeybees are sensitive to them. Humans have no direct perception of infrared rays, unlike the rattlesnake, which has receptors tuned in to wavelengths longer than 0.7 micron. The world would look eerily different if human eyes were sensitive to infrared radiation. Then, instead of the darkness of night we would be able to move easily in a strange, shadowless world where objects glowed with varying degrees of intensity. But human eyes excel in other ways. They are, in fact, remarkably discerning in color gradation. The color sensitivity of normal human vision is rarely surpassed even by sophisticated technical devices.

单选题Henry took a bus and headed home, ______ if his wife would have him back.

单选题The judge ruled that the evidence was inadmissible on the grounds that it was ______ to the issue at hand.

单选题Some esoteric fonts used by today"s artists emulate monks who copied medieval manuscripts by hand.

单选题The chairman suggested that everyone be present at the meeting ______ tomorrow morning.

单选题It has been recognized that the causes of premature births are multifarious, and it has been speculated that environmental______, such as stress, fear, exile, and inadequate prenatal maternal care, contribute to the rate of premature births.