Falling intonation indicates completeness and definiteness of the mentioned information, w

Which of the following can indicate that you need more sleep?

A．Falling asleep quickly.

B．Feeling tired in the afternoon occasionally.

C．Waking up early in the morning.

D．Feeling rested all day.

Look at the four squares,A ,B ,C , and D, which indicate where the following sentence could be added to the passage. Where would the sentence best fit?

Sophisticated plumbing was needed to service bathrooms and also to heat buildings with either steam or hot water.

A Skyscrapers differed from previous tall structures with their use of technical innovations such as cast iron and the elevator. The development of cast iron technology, in which molten iron is poured into a mold, made modem plumbing possible.B Cast iron pipes, fittings, and valves could deliver pressurized water to the many floors of tall buildings and drain wastewater out. The invention of the mechanical elevator made it possible to construct even taller buildings.C Before the elevator, office buildings were rarely more than four or five stories high. In 1857, the first passenger elevator equipped with safety brakes prevented the elevator from falling to the basement when a cable broke. The elevator made the upper floors as rentable as the first floor, liberating architecture from dependence on stairways and human muscle.D

A．Square Ａ.

B．Square Ｂ.

C．Square Ｃ.

D．Square Ｄ.

Which of the following is NOT mentioned as one of the most common reasons for injuries?

A. Skating with wrist and elbow wounds.

B. Losing one's balance due to road debris.

C. Being unable to stop due to high speed.

D. Falling down when doing a trick.

Niagara is an Indian word which means "roaring water", Indeed, the roar of the falling water of Niagara can be heard【1】a distance of 5kms, Imagine【2】of water flowing over a cliff 90 feet high and you will get an idea of that terrible noise. And【3】tremendous power the Niagara River has! It moves big rocks about and throws them into the boiling water below.【4】ago an old ship without single person on board was put in mid-stream. It sailed down the river【5】a toy boat with great speed. Having reached the fall, the ship dropped into the boiling water, never【6】again. There were some people who wanted to become famous【7】, swimming across the most dangerous part of the Niagara River. One of them was Captain Webb who said that he would try to swim cross the Niagara, which【8】crowds of people. On the evening of July 1st, 1893, Captain Webb came up to the river and【9】a plunge. His having jumped into the water【10】many people with horror. Soon, he appeared in the middle of the river. A loud shout went up from the crowd, but a moment later there was【11】silence. The man had disappeared under the water, Thousands of eyes【12】on the river, but the man was drowned. In 1902, a certain Miss Taylor decided to go over the falls in a barrel. There were different kinds of pillows inside the barrel to prevent her from【13】. Having examined the barrel carefully, Miss Taylor got in. The barrel was closed and then【14】into the water. Having reached the falls, it overturned and was shot down by the terrible【15】of the water. When the barrel was finally caught and opened, Miss Taylor came out alive【16】with a frightened look in her eyes. Once a crowd of visitors saw a rope【17】over from one bank of the river to the other. Then they saw a man【18】the rope. The man was an actor, Blondin【19】. He managed to cross Niagara Falls on a tight rope. The people on the bank were surprised at his【20】it so well.

(1)

A．within

B．inside

C．at

D．on

The ability of falling cats to right themselves in midair and land on their feet has been a source of wonder for ages. Biologists long regarded it as an example of【C1】______ by natural selection, but for physicists it bordered on the miraculous. Newton's laws of motion【C2】______ that the total amount of spin of a body cannot change【C3】______ an external torque speeds it up or slows it down. If a cat has no spin when it is released and experiences no external torque, it ought not to be able to 【C4】______ as it falls.

In the speed of its execution, the【C5】______ of a tumbling cat resembles a magician's trick. The gyrations of the cat in midair are【C6】______ fast for the human eye to follow, so the process is obscured. 【C7】______ the speeded up, or the cat's fall slowed down for the phenomenon to be former was accomplished 【C8】______ high-speed photography using equipment now【C9】______ in any pharmacy. But in the nineteenth century the【C10】______ on film of a falling cat constituted ascientific experiment.

The experiment was described in a paper presented to the Paris Academy in 1894. Two sequences of twenty photographs【C11】______ , one from the side and one from behind,【C12】______ a white cat in the act of righting itself. Grainy and quaint【C13】______ they are, the photos show that the cat was dropped upside down, with no initial spin, and still landed on its feet. Careful analysis of the photos reveals the secret. As the cat rotates the front of its body【C14】______ , the rear and tail twist counterclockwise,【C15】______ the total spin remains zero,【C16】______ Newton's laws. Halfway down, the cat pulls in its legs before reversing its twist and then extends them again,【C17】______ the desired end result. The explanation was that while no body can acquire spin without torque, a flexible one can readily change its【C18】______ Cats know this instinctively, but scientists could not be sure how it happened【C19】______ they increased the speed of their【C20】______ a thousand fold.

【C1】

A．adeptness

B．adaptation

C．adoption

D．adaptability

The ability of falling cats to right themselves in midair and land on their feet has been a source of wonder for ages. Biologists long regarded it as an example of 【C1】______ by natural selection, but for physicists it bordered on the miraculous. Newton's laws of motion 【C2】______ that the total amount of spin of a body cannot change 【C3】______ an external torque speeds it up or slows it down. If a cat has no spin when it is released and experiences no external torque, it ought not to be able to 【C4】______ as it falls.

In the speed of its execution, the 【C5】______ of a tumbling cat resembles a magician's trick. The gyrations of the cat in midair are 【C6】______ fast for the human eye to follow, so the process is obscured.【C7】______ the eye must be speeded up, or the cat's fall slowed down for the phenomenon to be observed. A century ago the former was accomplished 【C8】______ high-speed photography using equipment now 【C9】______ in any pharmacy. But in the nineteenth century the 【C10】______ on film of a falling cat constituted a scientific experiment.

The experiment was described in a paper presented to the Paris Academy in 1894. Two sequences of twenty photographs【C11】______ one from the side and one from behind, 【C12】______ a white cat in the act of righting itself. Grainy and quaint 【C13】______ they are, the photos show that the cat was dropped upside down, with no initial spin, and still landed on its feet. Careful analysis of the photos reveals the secret. As the Cat rotates the front of its body 【C14】______ , the rear and tail twist counterclockwise, 【C15】______ the total spin remains zero, 【C16】______ Newton's laws. Halfway down, the cat pulls in its legs before reversing its twist and then extends them again, 【C17】______ the desired end result. The explanation was that while no body can acquire spin without torque, a flexible one can readily change its 【C18】______ . Cats know this instinctively, but scientists could not be sure how it happened 【C19】______ they increased the speed of their 【C20】______ a thousandfold.

【C1】

A．adeptness

B．adaptation

C．adoption

D．adaptability

The ability of falling cats to right themselves in midair and land on their feet has been a source of wonder for ages. Biologists long regarded it as all example of 【C1】______ by natural selection, but for physicists it bordered on the miraculous. Newton's laws of motion 【C2】______ that the total amount of spin of a body cannot change 【C3】______ an external torque speeds it up or slows it down. If a cat has no spin when it is released and experiences no external torque, it ought not to be able to 【C4】______ as it falls. In the speed of its execution, the 【C5】______ of a tumbling cat resembles a magician's trick. The gyrations of the cat in midair are 【C6】______ fast for the human eye to follow, so the process is obscured. 【C7】______ the eye must be speeded up, or the cat's fall slowed down for the phenomenon to be observed. A century ago the former was accomplished 【C8】______ high-speed photography using equipment now 【C9】______ in any pharmacy. But in the nineteenth century the 【C10】______ on film of a falling cat constituted ascientific experiment. The experiment was described in a paper presented to the Paris Academy in 1894. Two sequences of twenty photographs 【C11】______ one from the side and one from behind, 【C12】______ a white cat in the act of righting itself. Grainy and quaint 【C13】______ they are, the photos show that the cat was dropped upside down, with no initial spin, and still landed on its feet. Careful analysis of the photos reveals the secret. As the cat rotates the front of its body 【C14】______ , the rear and tail twist counterclockwise, 【C15】______ the total spin remains zero, 【C16】______ Newton's laws. Halfway down, the cat pulls in its legs before reversing its twist and them extends them again, 【C17】______ he desired end result. The explanation was that while no body can acquire spin without torque, a flexible one can readily change its 【C18】______ . Cats know this instinctively, but scientists could not be sure how it happened 【C19】______ they increased the speed of their 【C20】______ a thousand fold.

【C1】

A．adeptness

B．adaptation

C．adoption

D．adaptability