单选题If the mother does not respond to her child's signals______.

单选题______ wrote "Shall I compare thee to a summer's day?" [A] John Milton [B] Francis Bacon [C] Christopher Marlowe [D] William Shakespeare

单选题According to the article, the life of Snow paralleled ______.

单选题[此试题无题干]

单选题 Questions 17 ～ 20 are based on a talk introducing Frank Wright. You now have 20 seconds to read Questions 17 ～ 20.

单选题 With human footprints on the moon, radio telescopes listening for messages from alien creatures (who may or may not exist), technicians looking for celestial and planetary sources of energy to support our civilization, orbiting telescopes' data hinting at planetary systems around other stars, and political groups trying to figure out how to save humanity from nuclear warfare that would damage life and eliminate on a planet-wide scale, an astronomy book published today enters a world different from the one that greeted books a generation ago. Astronomy has broadened to involve our basic circumstances and our mysterious future in the universe. With eclipses and space missions broadcast live, and with NASA, Europe, and the USSR planning and building permanent space stations, astronomy offers adventure for all people, an outward exploratory thrust that may one day be seen as an alternative to mindless consumerism, ideological bickering, and wars to control dwindling resources on a closed, finite Earth. Today's astronomy students not only seek an up-to-date summary of astronomical facts: they ask, as people have asked for ages, about our basic relations to the rest of the universe. They may study astronomy partly to seek points of contact between science and other human endeavors: philosophy, history, politics, environmental action, even the arts and religion. Science fiction writers and special effect artists on recent films help today's students realize that unseen worlds of space are real places—not abstract concepts. Today's students are citizens of a more real, more vast cosmos than conceptualized by students of a decade ago. In designing this edition, the Wadsworh editors and I have tried to respond to {{U}}these developments. {{/U}}Rather than jumping at the start into murky waters of cosmology, I have begun with the viewpoint of ancient people on Earth and worked outward across the universe. This method of organization automatically (if loosely) reflects the order of humanity's discoveries about astronomy and provides a unifying theme of increasing distance and scale.

单选题By the 1820's in the United States, when steamboats were common on western waters, these boats were mostly powered by engines built in the West (Pittsburgh, Cincinnati, or Louisville), and of a distinctive western design specially suited to western needs. The first steam engines (21) practical use in England and the United States were (22) low-pressure design. This was the type first (23) by James Watt, then manufactured by the firm of Boulton and Watt. Steam was (24) in a large, double-acting vertical cylinder, but the steam reached only a few pounds of pressure per square inch. It was low-pressure engines of this type that (25) first introduced into the United States by Robert Fulton. He (26) such a Boulton and Watt engine from England to run the Clermont. But this type of engine was ,expensive and complicated, (27) many precision-fitted moving parts. The engine that became standard on western steamboats was of a different and (28) design. It was the work primarily of an unsung hero of American industrial progress, Oliver Evans (1755-1819), the (29) son of a Delaware farmer. Evans early became (30) by the possibilities of mechanized production and steam power. As early as 1802 he (31) a stationary steam engine of high-pressure design in his mill. Engines of this type were not (32) , but before Evans they were generally considered (33) and dangerous. Within a decade the high-pressure engine, the new type, had become standard on western waters. Critics (34) of western conditions often attacked it as wasteful and dangerous. But people who really knew the Ohio, the Missouri, and the Mississippi (35) , with good reasons, that it was the only engine for them. In (36) western rivers the weight of vessel and engine (37) important; a heavy engine added to the problem of navigation. The high-pressure engine was (38) lighter in proportion to horsepower, and, with less than half as many moving parts, was much easier and cheaper to repair. The main advantages of low-pressure engines were safe operation and (39) of fuel consumption, (40) of which meant much in the West..

单选题What happens before the writer goes to bed?

单选题According to the text, which of the following people riding in the front does NOT have to wear a seat belt?

单选题Questions 11—13 are based on the following conversation between a driver and a police officer.

单选题In the 18th century, New York was smaller than Philadelphia and Boston. Today it is the largest city in America. How to explain the change in its size and importance? To answer this question we must consider certain facts about geography, history and economics. Together these three will explain the huge growth of America's most famous cities. The map of the Northeast shows that four of the most heavily-populated areas in this region are around seaports. At these points materials from across tile sea enter America, and the products of the land are sent there for export across the sea. Economists know that places where transportation lines meet are good places for making raw materials into completed goods, That is why seaports often have cities nearby. But cities like New York needed more than their geographical location in order to become great industrial centers. Their development did not happen simply by chance. About 1815, when many Americans from the east coast had already moved to the west. trade routes from the ports to the central regions of the country began to be a serious problem, The slow wagons of that time. drawn by horses or oxen, were too expensive for moving heavy freight very far. Americans had long admired Europe's canals. In New York State a canal seemed the best solution to the transportation problem From the eastern end of Lake Erie all the way across the state to the Hudson River there is a long trip of low land Here the Erie Canal was constructed. After working for several years it was completed in 1825. The canal produced an immediate effect. Freight costs were cut to about one-tenth of what they had been. New York City, which had been smaller than Philadelphia and Boston, quickly became the leading city of the coast. In later years, transportation routes on the Great Lakes were joined to routes on the Mississippi River. Then New York City became the end point of a great inland shipping system that emended from the Atlantic Ocean far up to the western branches of the Mississippi. The new railroads made canal shipping not as important as before, but it tied New York even more closely to the central regions of the country. It was easier for people in the central states to ship their goods to New York for export overseas. Exports from New York were greater than imports. Consequently, shipping companies were eager to fill their ships with passengers on the return trip from Europe. Passengers could come from Europe very cheaply as a result. Thus New York became the greatest port for receiving people from European countries. Many of them remained in the city. Others stayed in New York for a few weeks, months or years, and then moved to other parts of the United States. For these great numbers of new Americans. New York had to provide homes, goods and services. Their labor helped the city become great

单选题 {{I}}Questions 11-13 are based on the following talk. You now have 15 seconds to read Questions 11-13.{{/I}}

单选题From the last paragraph it can be concluded that the continuous growth of retired people