单选题 Scattered through the seas of the world are billions of tons of small plants and animals called plankton (浮游生物). Most of these plants and animals are too small for the human eye to see. They drift about lazily with the currents, providing a basic food for many larger animals. Plankton has been described as the equivalent of grasses that grow on the dry land continents, and the comparison is an appropriate one. In the potential food value, however, plankton far outweighs that of the land grasses. One scientist has estimated that while grasses of the world produce about 49 billion tons of valuable carbohydrates (碳水化合物) each year, the sea's plankton generates more than twice as much. Despite its enormous food potential, little effort was made until recently to farm plankton as we farm grasses on land. Now, marine scientists have at least begun to study this possibility, especially as the sea's resources appear even more important as a means of feeding an expanding world population. No one yet has seriously suggested the 'planktonburger' may soon become as popular as hamburger around the world. As a possible farmed supplementary food source, however, plankton is gaining considerable interest among marine scientists. One type of plankton that seems to have great harvest possibility is a tiny shrimp-like creature called krill (磷虾). Growing to two or three inches long, krill provide the major food for the giant blue whale, the largest animal on Earth. Realizing that this whale may grow to 100 feet and weigh 150 tons at maturity, it is not surprising that each one consumes more than one ton of krill daily. Krill swim about just below the surface in huge schools sometimes miles wide, mainly in the cold Antarctic. Because of their pink color, they often appear as a solid reddish mass when viewed from a ship or from air. Krill are very high in food value. A pound of them contains about 460 calories-about the same as shrimp or lobster, to which they are related. If the krill can feed such huge creatures as whales, many scientists reason, they must certainly be candidates as a new food source for humans.

单选题During the process, great care has to be taken to protect the ______ silk from damage. A. sensitive B. tender C. delicate D. sensible

单选题There is an old saying which goes, "Never ______ Until tomorrow what you can do today."

单选题British hopes of a gold medal in the Olympic Games suffered ______ yesterday, when Hunter failed to qualify during the preliminary heats.

单选题The passage wants to ______.

单选题Its so easy to walk into your first job and feel like a stranger in a strange land. But you donthave to stay that way ,and you shouldn t.You have to remind yourself to kick your shyness

单选题Something bad has happened ______ the family last night. A. to B. for C. of D. toward

单选题What's the language ______ in Germany?A. speakingB. spokenC. be spokenD. to speak

单选题The advanced life forms in nature are all symmetrical, instead of being ______ .

单选题A: How does your daughter like her new school? B: __________________ A. Fine. She seems to have made some new friends in no time. B. She likes it so much that she'll soon be reluctant to leave the school. C. Though she likes the new school, she loves her old school much stronger. D. Well, I'm afraid I don't know exactly.

单选题A: You seem to have a lot of work to do in your office. You've always been working overtime.B: ______

单选题Accustomed though we are to speaking of the films made before 1927 as 'silent', the film has never been, in the full sense of the word, silent. From the very beginning, music was regarded as an 27 accompaniment; when the Lumiere films were shown at the first public film exhibition in the United States in February 1896, they were 28 by piano improvisations (即兴创作) on popular tunes. At first, the music played 29 no special relationship to the films; an accompaniment of any kind was 30 . Within a very short time, however, the incongruity (不协调) of playing lively music to a 31 film became apparent, and film pianists began to take some care in 32 their pieces to the mood of the film. As movie theaters grew in number and importance, a violinist, and perhaps a cellist, would be added to the pianist in certain 33 , and in the larger movie theaters small orchestras were formed. For a number of years the selection of music for each film program 34 entirely in the hands of the conductor or leader of the orchestra, and very often the principal 35 for holding such a position was not skill or taste so much as the ownership of a large personal library of musical pieces. Since the conductor seldom saw the films until the night before they were to be shown, the musical arrangement was 36 improvised in the greatest hurry. A. sufficient B. incredible C. accompanied D. comparatively E. matching F. rested G. normally H. occasions I. bore J. qualification K. solemn L. indispensable M. severe N. according O. cases

单选题To be a good short story writer one needs, ______, a very vivid imagination.

单选题A trap ______ disguise is what has come to be called a Trojan Horse, from the ancient story of the gift of the wooden horse from the Greeks.

单选题Even the best medical treatment can not cure all the disease that ______ men and women.

单选题The agriculture production ______ is expected to double in northern part of China this year as a result of a sufficient rain fall in the spring and the new privileged policy for the farmers.

单选题One of the responsibilities of the Coast Guard is to make sure that all ships ______ follow traffic rules in busy harbors.

单选题Even if they are on sale, these refrigerators are equal in price to, if not more expensive than, _______ at the other store.