You can’t complain about being left out ______you don’t make any effort to share your joys and sorrows with others.
A. once B. unless C. when D. though
科目：高中英语 来源：2013-2014学年陕西省高三第七次适应性训练英语试卷（解析版） 题型：单项填空
_______ I went to the South Lake in Hanzhong, I was deeply impressed with its beautiful scenery.
A. For the first time B. The first time
C. At first D. It was the first time
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科目：高中英语 来源：2013-2014学年重庆市高三二诊模拟英语试卷（解析版） 题型：单项填空
-- Has he apologized for his rudeness?
-- __________ .
A．No doubtB．No luckC．Not yetD．Not exactly
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科目：高中英语 来源：2013-2014学年重庆市高三4月月考英语试卷（解析版） 题型：阅读理解
Most people know precious gemstones (宝石) by their appearances. An emerald flashes deep green, a ruby seems to hold a red fire inside, and a diamond shines like a star. It’s more difficult to tell where the gem was mined, since a diamond from Australia or Arkansas may appear the same to one from the Democratic Republic of the Congo. However, recently, a team of scientists has found a way to identify a gemstone’s origin.
Beneath the surface of a gemstone, on the tiny level of atoms and molecules, lie clues to its origin. At this year’s meeting of the Geological Society of America in Minneapolis, Catherine McManus reported on a technique that uses lasers to clarify these clues and identify a stone’s homeland. McManus directs scientific research at Materialytics, in Killeen, Texas. The company is developing the technique. “With enough data, we could identify which country, which mining place, even the individual mine a gemstone comes from,” McManus told Science News.
Some gemstones, including many diamonds, come from war-torn countries. Sales of those “blood minerals” may encourage violent civil wars where innocent people are injured or killed. In an effort to reduce the trade in blood minerals, the U.S. government passed law in July 2010 that requires companies that sell gemstones to determine the origins of their stones.
To figure out where gemstones come from, McManus and her team focus a powerful laser on a small sample of the gemstone. The technique is called laser-induced breakdown spectroscopy. Just as heat can turn ice into water or water into steam, energy from the laser changes the state of matter of the stone. The laser changes a miniscule part of the gemstone into plasma, a gas state of matter in which tiny particles called electrons separate from atoms.
The plasma, which is superhot, produces a light pattern. (The science of analyzing this kind of light pattern is called spectroscopy.) Different elements produce different patterns, but McManus and her team say that gemstones from the same area produce similar patterns. Materialytics has already collected patterns from thousands of gemstones, including more than 200 from diamonds. They can compare the light pattern from an unknown gemstone to patterns they do know and look for a match. The light pattern acts like a signature, telling the researchers the origin of the gemstone.
In a small test, the laser technique correctly identified the origins of 95 out of every 100 diamonds. For gemstones like emeralds and rubies, the technique proved successful for 98 out of every 100 stones. The scientists need to collect and analyze more samples, including those from war-torn countries, before the tool is ready for commercial use.
Scientists like Barbara Dutrow, a mineralogist from Louisiana State University in Baton Rouge, find the technique exciting. “This is a basic new tool that could provide a better fingerprint of a material from a particular locality,” she told Science News.
1.We learn from Paragraph 1 that __________________.
A. an emerald and a ruby are names of diamonds.
B. it’s not difficult to tell where the gem was mined.
C. appearances help to identify the origin of gemstones.
D. diamonds from different places may appear the same.
2.Why did the U.S. government pass law that requires companies selling gemstones to determine the origins of their stones?
A. To look for more gemstones.
B. To encourage violent civil wars.
C. To reduce the trade in blood minerals.
D. To develop the economy.
3.Which of the following facts most probably helps McManus and her team in identifying the origin of stones?
A. Heat can turn ice into water or water into steam.
B. Gemstones from the same area produce similar light patterns.
C. Laser can changes a miniscule part of the gemstone into plasma.
D. Materialytics has already collected patterns from thousands of gemstones.
4.From the last two paragraphs, what can be inferred about the laser technique?
A. It is ready for commercial use.
B. People can use the new tool to find more gemstones.
C. It can significantly reduce the gemstones trade in blood minerals.
D. It will bring about a revolutionary change in identifying the origin of minerals.
5.The author wrote this passage mainly to ________.
A. tell us how to identify the origin of diamonds.
B. introduce a laser technique in identifying a stone’s origin
C. prove identifying the origin of gemstones are difficult
D. attract our attention to reducing trade in blood minerals
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科目：高中英语 来源：2013-2014学年重庆市高三4月月考英语试卷（解析版） 题型：单项填空
Everyone in this country should work hard and do what they can _____ against national smog.
A. fight B. foughtC. fightingD. to fight
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科目：高中英语 来源：2013-2014学年重庆市高三4月月考英语试卷（解析版） 题型：单项填空
— Tom, could you give me a hand in the following exam?
— ______ . Mom won’t allow me to do such crazy things.
A. No problem B. It's a pleasure C. Forget it D. My pleasure
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科目：高中英语 来源：2013-2014学年辽宁省锦州市高三第一次质量检测考试英语试卷（解析版） 题型：填空题
阅读下面材料，在空白处填入适当的内容（不多于3 个单词） 或括号内单词的正确形式。
A young and successful manager was travelling down a neighborhood street, going a bit too fast in his new Jaguar, 1.a brick hit the door of his Jaguar．
He jumped out of the car, 2.（seize） some kid and pushed him up against the parked car, shouting, “That’s 3.new car and that brick you threw is going to cost a lot of 4.．Why did you do it?” “I’m sorry．I didn’t know what else to do?” begged the youngster．
“It’s my brother,”he said．“ He fell out of his wheelchair and I can’t lift him up．” 
Sobbing, the boy asked the manager, “5.you please help me get 6.back into his wheelchair? He 7.（hurt）, and he’s too heavy for me”．
8.（move） beyond words, he lifted the young man back into the wheelchair back and took out his handkercheif and wiped thepes and cuts, 9.（check） to see that everything was going to be okay．
“Thank you, sir．And God bless you．”the grateful child said to him and then pushed his brother down the sidewalk 10.their home．
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科目：高中英语 来源：2013-2014学年贵州省第一学期高三第三次月考英语试卷（解析版） 题型：短文改错
假定英语课上老师要求同桌之间交换修改作文，请你修改你同桌写的以下作文。文中共有10处语言错误，每句中最多有两处，每处错误仅涉及一个单词的增加、删除或修改。
增加：在缺词处加一个漏字符号（∧），并在其下面写出该加的词。
删除：把多余的词用斜线（\）划掉。
修改：在错的词下划一横线，
并在该词下面写出修改后的词。
注意：1．每处错误及其修改均限一词。
2．只允许修改10处，多者（从第11处起）不计分。
Jim arrived in home and discovered that he has forgotten his door key．He rang the bell, but nobody came to open the door．He rang again and waiting, but still there was not reply．He walked round the house to see if he could find the open window, but they were all locked．It was beginning to rain, he did not know how to do．Kate, his wife, had obvious gone out．He didn’t know where she had gone or when she would return．Finally, picked up a stone, he threw them at the kitchen window．Just then, his wife came back．
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科目：高中英语 来源：2013-2014学年福建省高三第六次月考英语试卷（解析版） 题型：单项填空
Because something unexpected , the famous singer had to put off her schedule.
A. came up B. cleared up
C. stayed up D. ended up
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