填空题Smog-choked Southern California demands them. It's a car for people who never want to go to a gas station again. But the fact is, for all the talk, selling gasless machines has been a hard-sell.A.demandsB.aC.aslessD.hard-sell

填空题On a summer evening I was caught in the crossfire of dueling wood thrushes, each defending his portion of the forest. Their chosen weapons were their voices; melodies were their ammunition. Each sought to wound the other's pride, but their sweet fluting pierced only the evening silence. (71) I doubt that the duelists saw one another, because the wood thrush is content to pour out his nocturne from the middle of a low limb draped by leaves. He needs no approving audience and can project his voice without resorting to a singing perch in the treetop. The brown-backed, speckle-breasted, eight-inch wood thrush only looks drab. All of his beauty is concentrated in his voice. Let the scarlet tanager take the prize as the forest's flashiest dresser. Among his winged brethren, the song of the wood thrush has no equal. He sings more enchantingly than any bird I know. (72) On the trail, I often find myself stopping to admire the wood thrush's gift. After wintering mainly in Mexico and Central America, wood thrushes return north to breed. The male's echoing melody challenges his rivals, wakes the raccoon and serenades the woodland sojourner. In California they don't hear wood thrushes, which in summer occur only in the eastern forest. It's enough to prevent me from moving West. (73) While traveling in Europe, John James Audubon got homesick for "the sweet melodious strains of that lovely recluse, my greatest favorite, the Wood Thrush." Henry David Thoreau said, "He touches a depth in me which no other bird's song does," and he called the wood thrush "a Shakespeare among birds." Ancient magic lives on in the woods. (74) The Pilgrims must have heard it, too, and perhaps the wood thrush comforted them in their wild new world. The wood thrush's song consists of several phrases, variations on his basic ee-o-lay theme, in quality like a flute but richer, not airy. Each phrase usually concludes with a high-pitched chord. Throaty utterings audible at close range may introduce the next phrase. The song's ending is sometimes marked by a downsliding note that slows and trails off. After a pause, the song is repeated. Occasionally, the wood thrush launches into a series of sustained intonations, a haunting counterpoint to his primary song. (75) Some are almost mechanical, others merely sweet--the inspired wood thrush sings with a certain soulfulness. He plays his fine vocal instrument with great sweetness, yet there is an undercurrent of sadness. He speaks to me of struggle and survival, of loss and rebirth, and ultimately of hope. He awakens me to the indefinable yearnings that humans and wood thrashes share.A. A special gene make certain wood thrushes exceptional.B. Lyrical, liquid and loud, his voice has beauty and depth to match nature's.C. There is wide variation in the singing ability of wood thrushes.D. I was moved, but both wood thrushes stood their ground.E. You can go there and hear what Audubon and Thoreau heard, the same song Native Americans heard in the virgin forest.F. His singular talent won this common bird the unabashed affection of two of America's foremost naturalists, an artist and a writer.

填空题Hitler wanted to invade England (56) could not do so until the RAF was destroyed. In August 1940 the Germans began daylight bombing against English ports and airfields and in September (57) London and other cities. The plan was to draw out the English fighters and destroy them. (58) the RAF was very small, the people of England were praying for the fighter pilots and believing (59) an English victory. The Nazis started losing a great (60) of their airplanes and changed (61) to night bombing by the end of September. The people of London were also in the front lines (62) they couldn't fly fighters and smash the enemy planes. They had to dig quickly in cellars to (63) their friends who had been buried underneath the wreckage. They had to put out endless fires. They had to stand (64) and take whatever the enemy threw at them. People understood that Britain's fate depended on the resolution of the common people, and those watching for fire on the roofs. This continued (65) the Nazis were finally defeated by the Allied nations.

填空题One word that you might have learned when you were studying about sound is frequency. Frequency means 1 fast the sound wave vibrates. Faster vibrations produce 2 pitched sounds. The notes in a musical scale indicate the 3 or frequency of the sound. 4 word that can describe a sound is intensity. Intensity 5 to the amount of energy in a sound wave, and it 6 a sound"s loudness. Printed music will often include notes about how loud or 7 to play each section of the music. Timbre is another 8 used to describe musical sounds. It describes how the same note will have 9 sounds when played 10 different instruments. For example the same note may sound soft and pretty when played on a flute, 11 strong and brassy when played on a trumpet. The timbre of a note comes from both the actual note 12 is played 13 also its overtones, 14 are other higher and lower sounds that are produced 15 the same time.

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填空题There (is) much in our life (which) we do not control (and we are) not even responsible (for). A. is B. which C. and we are D. for

填空题No one (care about) if he (appears) at the meeting next year or not. If (it happens) he will (be made to) apologize for his careless comments. A. care about B. appears C. it happens D. be made

填空题A. The new Minneapolis bridge joins a handful of "smart" bridges that have built-in sensors to monitor their health. B. The kilometers of wire needed to connect sensors to central computers can add significantly to the system's cost, according to Jerome Lynch of the University of Michigan, Ann Arbor. C. By 2025 all bridges in America will have been equipped with this advanced technology. D. A continuous skin would solve this problem. E. In the wake of the catastrophe, there were calls to harness technology to avoid similar mishaps. F. Engineers then installed additional weights as dampeners. When an eight-lane steel-truss-arch bridge across the Mississippi River in Minneapolis collapsed during the evening rush hour on August 1st 2007, 13 people were killed and 145 were injured. There had been no warning. The bridge was 40 years old but had a life expectancy of 50 years. The central span suddenly gave way after the gusset plates that connected the steel beams buckled and fractured, dropping the bridge into the river. (71) The St. Anthony Falls bridge, which opened on September 18th, 2008 and replaces the collapsed structure, should do just that. It has an embedded early-warning system made of hundreds of sensors. They include wire and fibre-optic strain and displacement gauges, accelerometers, potentiometers and corrosion sensors that have been built into the span to monitor it for structural weaknesses, such as corroded concrete and overly strained joints. (72) Another example is the six-lane Charilaos Trikoupis bridge in Greece, which spans the Gulf of Corinth, linking the town of Rio on the Peloponnese peninsula to Antirrio on the mainland. This 3km-long bridge, which was opened in 2004, has roughly 300 sensors that alert its operators if an earthquake or high winds warrant it being shut to traffic, as well as monitoring its overall health. These sensors have already detected some abnormal vibrations in the cables holding the bridge. (73) The next generation of sensors to monitor bridge health will be even more sophisticated. For one thing, they will be wireless, which will make installing them a lot cheaper. (74) Dr Lynch is the chief researcher on a project intended to help design the next generation of monitoring systems for bridges. He and his colleagues are also looking at how to make a cement-based sensing skin that can detect excessive strain in bridges. Individual sensors, says Dr Lynch, are not ideal because the initial cracks in a bridge may not occur at the point the sensor is placed. (75) He is also exploring a paint-like substance made of carbon nanotubes that can be painted onto bridges to detect corrosion and cracks. Since carbon nanotubes conduct electricity, sending a current through the paint would help engineers to detect structural weakness through changes in the paint's electrical properties.

填空题What is the result of the "new form of discrimination" (Line 5, Para 4)?

填空题What is kinesics?