軎（wei）与辖：

To my regret, your explanation is ______ (satisfaction).

unsatisfactory

As Wei Hua got another "C" in the English test, her parents looked ______ at him, holding the school report.

A:sad B:sadly C:happy D:happily

Language Learning
It is, everyone agrees, a huge task that the child performs when he learns to speak, and the fact that he does so in so short a period of time challenges explanation.
Language learning begins with listening. Individual children vary greatly in the amount of listening they do before they start speaking, and late starters are often long listeners. Most children will "obey" spoken instructions some time before they can speak, though the word obey is hardly accurate as a description of the eager and delighted cooperation usually shown by the child. Before they can speak, many children will also ask questions by gesture and by making questioning noises.
Any attempt to trace the development from the noises babies make to their first spoken words leads to considerable difficulties. It is agreed that they enjoy making noises, and that during the first few months one or two noises sort themselves out as particularly indicative of delight, distress, sociability, and so on. But since these cannot be said to show the baby’s intention to communicate, they can hardly be regarded as early forms of language. It is agreed, too, that from about three months they play with sounds for enjoyment, and that by six months they are able to add new sounds to their repertoire (能发出的全部声音). This self-imitation leads on to deliberate (有意识的) imitation of sounds made or words spoken to them by other people. The problem then arises as to the point at which one can say that these imitations can be considered as speech.

By "... challenges explanation" (Line 2, Para. 1)the author means that （　）.

A:no explanation is necessary for such an obvious phenomenon B:no explanation has been made up to now C:it’s no easy job to provide an adequate explanation D:it’s high time that an explanation was provided

? ?Scientists say they have discovered hints of alien life on the Saturn’s moon. The discovery of a sort of life was announced after researchers at the US space agency, NASA, analyzed data from spacecraft Cassini, which pointed to the existence of methane-based form of life on Saturn’s biggest moon.
? ?Scientists have reportedly discovered clues showing primitive alien beings are "breathing" in Titan’s dense atmosphere filled with hydrogen.
? ?They argue that hydrogen gets absorbed before hitting Titan’s planet-like surface covered with methane lakes and rivers. This, they say, points to the existence of some "bugs" consuming the hydrogen at the surface of the moon less than half the size of the Earth.
? ?"We suggested hydrogen consumption because it’s the obvious gas for life to consume on Titan, similar to the way we consume oxygen on Earth," says NASA scientist Chris McKay. "If these signs do turn out to be a sign of life, it would be doubly exciting because it would represent a second form of life independent from water-based life on Earth. "
? ?To date, scientists have not yet detected this form of life anywhere, though there are liq-uid-water-based microorganisms on Earth that grow well on methane or produce it as a waste product. On Titan, where temperatures are around 90 Kelvin (minus 290 degrees Farenheit), a methane-based organism would have to use a substance that is liquid as its medium for living processes, but not water itself. Water is frozen solid on Titan’s surface and much too cold to support life as we know it.
? ?Scientists had expected the Sun’s interactions with chemicals in the atmosphere to produce a coating of acetylene on Titan’s surface. But Cassini detected no acetylene on the surface.
? ?The absence of detectable acetylene on the Titan’s surface can very well have a non-bio-logical explanation, said Mark Allen, a principal investigator of the NASA Titan team.
? ?"Scientific conservatism suggests that a biological explanation should be the last choice after all non-biological explanations are addressed," Alien said. "We have a lot of work to do to rule out possible non-biological explanations. It is more likely that a chemical process, without biology, can explain these results. /

What can be inferred from what Allen said?

A:Scientists have different arguments over whether there is life on Titan. B:Scientists all agree that a non-biological chemical reaction is a possible explanation. C:Scientists all suggest that a biological explanation is reasonable. D:Scientists all agree that there is life on Titan.

? ?下面有3篇短文，每篇短文后有5道题，每题后面有4个选项。请仔细阅读短文并根据短文回答其后面的问题，从4个选项中选择1个最佳答案。
{{B}}第一篇{{/B}}

By "... challenges explanation" (Line 2, Para. 1)the author means that ______.

A:no explanation is necessary for such an obvious phenomenon B:no explanation has been made up to now C:it’s no easy job to provide an adequate explanation D:it’s high time that an explanation was provided

第三篇"Life Form Found" on Saturn’s Titan Scientists say they have discovered hints of alien life on the Saturn’s moon. The discovery of a sort of life was announced after researchers at the US space agency, NASA, analyzed data from spacecraft Cassini, which pointed to the existence of methane-based form of life on Saturn’s biggest moon. Scientists have reportedly discovered clues showing primitive alien beings are "breathing" in Titan’s dense atmosphere filled with hydrogen. They argue that hydrogen gets absorbed before hitting Titan’s planet-like surface covered with methane lakes and rivers. This, they say, points to the existence of some "bugs" consuming the hydrogen at the surface of the moon less than half the size of the Earth. "We suggested hydrogen consumption because it’s the obvious gas for life to consume on Titan, similar to the way we consume oxygen on Earth," says NASA scientist Chris McKay. "If these signs do turn out to be a sign of life, it would be doubly exciting because it would represent a second form of life independent from water-based life on Earth." To date, scientists have not yet detected this form of life anywhere, though there are liquid-water-based microorganisms on Earth that grow well on methane or produce it as a waste product. On Titan, where temperatures are around 90 Kelvin (minus 290 degrees Fahrenheit), a methane-based organism would have to use a substance that is liquid as its medium for living processes, but not water itself. Water is frozen solid on Titan’s surface and much too cold to support life as we know it. Scientists had expected the Sun’s interactions with chemicals in the atmosphere to produce a coating of acetylene on Titan’s surface. But Cassini detected no acetylene on the surface. The absence of detectable acetylene on the Titan’s surface can very well have a non-biological explanation, said Mark Allen, a principal investigator of the NASA Titan team. "Scientific conservatism suggests that a biological explanation should be the last choice after all non-biological explanations are addressed." Allen said. "We have a lot of work to do to rule out possible non-biological explanations. It is more likely that a chemical process, without biology, can explain these results." It can be inferred from Mark Allen’s address that

A:Scientists are trying to conform there is life on Titan. B:Scientists agree that a chemical reaction is a convincing explanation. C:Scientists share the opinion that a biological explanation is reasonable. D:Scientists are arguing over whether there is life on Titan.

Wei Mingzhi, agirl, takes Mr. Gaos place in the primary school.

A:thirteenyearold B:thirteenyearsold C:thirteen year old D:thirteen years old

Wei Mingzhi, agirl, takes Mr. Gaos place in the primary school.

A:thirteenyearold B:thirteenyearsold C:thirteen year old D:thirteen years old