Many people are aware of the beauty of a solar eclipse (日食), but are surprised to learn that lunar eclipses are often just as impressive. While total solar eclipse lasts only for a few minutes and can be seen only in a small area of a few kilometers, total lunar eclipse can last for several hours and can be seen over much of the planet. In fact, the beauty and stability of lunar eclipses make them a favorite of both amateur and professional photographers.
Lunar eclipses generally occur two or three times a year, and are possible only when the Moon is full. When we see the Moon, we are actually seeing sunlight reflected off the surface of the Moon When the Earth is positioned in between the Moon and the Sun, however, the Earth's shadow falls on the Moon, and a lunar eclipse occurs.
The type of lunar eclipse - total, partial, or penumbral (半影) - that occurs depends both on how much of the Moon passes through the Earth's shadow and through which part of the shadow it passes. A penumbral eclipse occurs when the Moon passes through the Earth's outer shadow. This type of eclipse is brief and frequently goes unobserved by all but astronomers. By contrast, total and partial eclipses occur when all or part, respectively, of the Moon passes through the umbra(本影) shadow of the Earth. These eclipses are quite easy to see and are widely observed.
Unlike solar eclipses, lunar eclipses are safe to watch. Solar radiation that occurs during an eclipse of the Sun can cause a form of burns of one's eyes known as eclipse blindness. In fact, the only way to safely view a solar eclipse is by using specially designed equipment. However, since the Moon's light is reflected sunlight, it is completely safe to watch a lunar eclipse without any special equipment, although a pair of binoculars can certainly help the viewer appreciate the beauty of this phenomenon
小題1:The underlined word "stability " most probably means_______.
A.strengthB.positionC.steadinessD.visibility
小題2:According to the passage, a partial lunar eclipse occurs________.
A.when the Moon passes between the Sun and the Earth
B.when all of the Moon passes through the Earth's umbra shadow
C.when only a part of the Moon passes through the Earth's outer shadow
D.when only a part of the Moon passes through the Earth's umbra shadow
小題3:The passage implies that penumbral eclipses are________.
A.longer-lasting than most solar eclipses
B.more common than partial or full lunar eclipse
C.the result of the shadow cast by the Moon onto the Earth
D.more difficult to observe than other types of lunar eclipse
小題4:According to the passage, it is safe to watch a lunar eclipse, unlike a solar eclipse, because ________.
A.moonlight is less strong than sunlight
B.a(chǎn) lunar eclipse is briefer than a solar eclipse
C.a(chǎn) lunar eclipse lasts much longer than a solar eclipse
D.special equipment can be employed to view a lunar eclipse

小題1:C
小題2:D
小題3:D
小題4:A

試題分析:
本文介紹了月食發(fā)生的條件、月食的類型和觀看。月食只能在滿月時發(fā)生,有月全食、月偏食和半影月食三種情形:月全食指月球全部進入地球本影,月偏食指月球部分進入地球本影,半影月食指月球離地球較遠、只是從地球本影最外緣掠過;觀看月食是完全安全的,無需設(shè)備。
小題1:詞義推斷題。第一段…total lunar eclipse can last for several hours and can be seen over much of the planet.說的是月全食時間上的持久性和可見區(qū)域的廣闊性。這種特性使其成為專業(yè)攝影師和業(yè)余攝影愛好者的最愛。stability指的是月全食在時間上的持久穩(wěn)定,詞義與steadiness相近,故C項正確。
小題2:細節(jié)題。如出現(xiàn)A項描述的情況,會發(fā)生日食;B項情況出現(xiàn)會發(fā)生月全食;C項情況出現(xiàn)發(fā)生半影月食,即月球從地球本影外緣經(jīng)過,此時月球光線略略變暗,很難被人注意。由第三段…total and partial eclipses occur when all or part, respectively, of the Moon passes through the umbra shadow of the Earth. 可知,月球全部進入地球本影發(fā)生月全食,部分進入地球本影發(fā)生月偏食。故D項正確。
小題3:細節(jié)題。由A penumbral eclipse occurs when the Moon passes through the Earth's outer shadow. This type of eclipse is brief and frequently goes unobserved by all but astronomers.可知,半影月食時間短,經(jīng)常不為人注意。故選擇D項。
小題4:細節(jié)題。最后一段…since the Moon's light is reflected sunlight, it is completely safe to watch a lunar eclipse without any special equipment告訴我們,月光是太陽光的折射,所以觀察月食是絕對安全的。原因只能是月光比太陽光線弱。選擇A項。
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科目:高中英語 來源:不詳 題型:閱讀理解

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小題1:What’s the best title for this passage?
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B.Homemade CPUs with a Long Way to Go
C.The Supercomputers of Three Organizations in China
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Researchers at government and university labs all over the country are trying to figure out why so many bees are dying. However, bees are hard to study. Most die away from the hive, so researchers don’t have dead bodies to examine. And when researchers return to a hive after two weeks, about half the bees they studied on their first visit will be dead, replaced by new ones in the natural life cycle of bees. “It isn’t like studying a large animal like a cow that doesn’t move around much and is easy to find out in the cow field,” says Pettis.
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B.many famous US universities are considering adopting the “three-year degree” model
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D.some excellent students can graduate ahead of time
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A.the author is a college professor
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D.the author pays special attention to the all-round development of college students
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科目:高中英語 來源:不詳 題型:閱讀理解

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It is easy to find organic mulch materials. Cut-up leaves and small pieces of tree bark can be used. Grass cuttings are also a good mulch for plants. Mulch from news- papers works well in controlling weeds.
The best time to add mulch depends on your goal. Mulch provides a thick barrier between the soil and the air. This helps to reduce temperature changes in the soil. As a result, mulched soil will be cooler than other soil in the summer. In winter, the mulched soil may not freeze as deeply as other soil. The best time is after the ground has frozen, but before the coldest weather arrives. Spreading mulch before the ground has frozen may attract small animals searching for a warm place to spend the winter. Delaying the spreading should prevent this problem. The animals will probably find another place to live.
小題1:The author tells us the following EXCEPT ______.
A.what mulch is and its advantages
B.the best time to add mulch
C.the bad effects of mulch
D.what can be mulch on the soil surface
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A.tree barksB.plasticC.grass cuttingsD.cut-up leaves
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B.improve the ability of the soil to hold water
C.provide a good environment for earthworms
D.improve the growth of roots and increase the movement of water through the soil
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A.the best time to add mulch is in spring and summer
B.the best time to add mulch is after the coldest weather arrives
C.the best time to add mulch is exactly the same time of each year
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