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单选题How was her flight to Australia?
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单选题The author doesn't agree that ______.
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单选题In which case will mother be serving "noodles" ?
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单选题Living here at the top of the mountain with no one else nearby, you must be very ______.
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单选题{{B}}Passage Two{{/B}} The bat is a marvel of evolutionary adaptation. Most of them roost during the day, and are active at night or twilight for they can avoid objects in the dark. I have seen this phenomenon at work. In my youth I used to explore old mining shafts in the Randsburg district. Sometimes my intrusion disturbed clans of bats that were hanging upside down in the dark caves. They would fly about to evident panic, but the panic was mine, not theirs. Some flew crazily out into the daylight but some merely returned to their perches. None ever touched me, much to my relief. They may exist but I have never seen a stuffed nylon bat. To children, bats may not be as lovable as koala bears. Perhaps manufacturers do not regard them as marketable. It is not so much their hideous faces and winged bodies that have caused us to get rid of bats, but rather the ancient myths in which dead humans, such as Count Dracula, leave their graves at night in the form of bats to suck blood from human victims, especially fragile young woman. As we know from some movies these vampires must return to their graves before daylight. Endangered young women can frustrate vampire by sleeping with a string of garlic around their necks. There are actually three species of bloodsucking bats. They are called vampire bats after the ancient legends, and their tactics are indeed frightful. Like Count Dracula, they feed at night. They make a small cut in their sleeping victim with sharp incisor teeth, usually not even awakening their prey. Then they suck the blood that sustains them. Should that discourage children from wanting them as pets? As Mitchell notes from the New 'Yorker ad, bats are clean and intelligent. Most of them are insect-eaters, and they serve nature by destroying crop-damaging insects. They also pollinate (传授花粉) flowers and spreading seed. Bat Conservation International claims that without bats a host of insects/pests would multiply unchecked and many of our planet's most valuable plants would go unpollinated. It is clear that the bat is our friend, and that, despite its appearance, it is here to serve humanity. I'd be the first to buy a stuffed nylon bat. Children's hearts are big, and bats need love, too.
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单选题______! You should take this chance to attend it.A.How important conference is itB.How an important conference it isC.What an important conference is itD.What an important conference it is
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单选题 While still in its early stages, welfare reform has already been judged a great success in many states, at least in getting people off welfare. It's estimated that more than 2 million people have left the rolls since 1994. In the past four years, welfare rolls in Athens County have been cut in half. But 70 percent of the people who left in the past two years took jobs that paid less than $ 6 an hour. The result: The Athens County poverty rate still remains at more than 30 percent—twice the national average. For advocates (代言人) for the poor, that's an indication much more needs to be done. "More people are getting jobs, but it's not making their lives any better. " says Kathy Lairn, a policy analyst at the Center on Budget and Policy Priorities in Washington. A center analysis of U. S. Census data nationwide found that between 1995 and 1996, a greater percentage of single, female-headed households were earning money on their own, but that average income for these households actually went down. But for many, the fact that poor people are able to support themselves almost as well without government aid as they did with it is in itself a huge victory. "Welfare was a poison. It was a toxin (毒素) that was poisoning the family. " says Robert Rector, a welfare-reform policy analyst. "The reform is changing the moral climate in low-income communities. It's beginning to rebuild the work ethic (道德观), which is much more important. " Mr. Rector and others argued that once "the habit of dependency is cracked," then the country can make other policy changes aimed at improving living standards.
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单选题The new______machine is a great help in the production of this factory.
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单选题He looked around and caught a man ______ his hand into the pocket of a passenger. A.to be putting B.putting C.to put D.put
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单选题The idea is as audacious as it altruistic: provide a personal laptop computer to every schoolchild—particularly in the poorest parts of the world. The first step to making that happen is whittling the price down to $100. And that is the goal of a group of American techno-gurus led by Nicholas Negroponte, the founder of the fabled MIT Media Lab. When he unveiled the idea at the World Economic Forum in January it seemed wildly ambitious. But surprisingly, it is starting to become a reality. Mr. Negroponte plans to display the first prototype in November at a UN summit. Four countries—Brazil, Egypt, Thailand and South Africa—have said they will buy over l m units each. Production is due to start in late 2006. How is the group, called One Laptop Per Child (OLPC), able to create a laptop so inexpensively? It is mainly a matter of cleverly combining existing technologies in new ways. The laptop will have a basic processor made by AMD, flash memory instead of a hard disk, will be powered by batteries or a hand-crank, and will run open-source software. The $100 laptop also puts all the components behind the screen, not under the keyboard, so there is no need for an expensive hinge. So far, OLPC has got the price down to around $130. But good news for the world"s poor, may not be such great news for the world"s computer manufacturers. The new machine is not simply of interest in the developing world. On September 22nd, Mitt Romney, the governor of Massachusetts, said the state should purchase one for every secondary-school student, when they become available. Sales to schools are just one way in which the $100 laptop could change the computer industry more broadly. By depressing prices and fuelling the trend for "good-enough computing", where customers upgrade less often, it could eventually put pressure on the world"s biggest PC-makers.
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单选题______ do it ourselves, will you?
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单选题The volume of the sun is about 1300000 ______ that of the earth. A) time B) times C) time in D) time of
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单选题It is impossible to ______ this battle, for it raged for six months.
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单选题— Who is that gentleman who talked to you just now? — He is my uncle ______ marriage.A. atB. toC. byD. with
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单选题Scraps of food could soon be helping power your home, thanks to an ultra-cheap bacteria-driven battery. Its developers hope that instead of feeding the dog or making garden compost(混合肥料) ,organic household waste could top up your home's electricity. Although such "microbial fuel cells" (MFCs)have been developed in the past, they have always proved extremely inefficient and expensive. Now Chris Melhuish and technologists at the University of the West of England(UWE)in Bristol have come up with a simplified MFC that costs as little as £10 to make. Right now, their fuel cell runs only on sugar cubes, since these produce almost no waste when broken down, but they aim to move on to carrot power. "It has to be able to use raw materials, rather than giving it a refined fuel," says Melhuish. Inside the Walkman-sized battery, a colony of E. coil bacteria produce enzymes that break down carbohydrates, releasing hydrogen atoms. The cell also contains chemicals that drive a series of redox, or reduction and oxidation reactions, stripping electrons from the hydrogen atoms and delivering them steadily to the fuel cell's anode(正极). This creates a voltage that can be used to power a circuit. To prove the MFC works, the researchers are using it to power a small light-sensitive robot. And when a number of the cells are connected in series, they could power domestic appliances, running a 40-watt bulb for eight hours on about 50 grams of sugar. Earlier MFCs were inefficient because they relied on energy-hungry filters and pumps. By experimenting with different anode materials, the UWE team have figured out how to make their system work: they dump the bacteria and redox chemicals directly into the cell. In its current form, the UWE team says its organic battery can produce eight times as much power as any previous MFC. But Melhuish wants to improve this, both by scaling it up and finding a better mix of redox chemicals.
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单选题[此试题无题干]
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单选题Since the energy crisis, these big cars have become a real liability. They cost too much to run. A. lack of reliability B. substitute C. costly means of transport D. disadvantage
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单选题The engine of the ship was out of order and the bad weather ______ the helpless of the crew at sea.A. added toB. resulted fromC. turned outD. made up
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