读“我国的西北地区荒漠化”及“荒漠化发展与结果”图，回答下列问题：（15分）
（1）我国西北地区最为显著的自然特征是 。随距海里程的增加，本区自东向西降水 ，干旱程度 。这在很大程度上决定西北区为我国生态环境最为脆弱地区。（3分）
（2）从“荒漠化的发展与结果”图中看出，土地荒漠化的最终结果是 的长期丧失，其实质是 的退化。（2分）
（3）简述西北荒漠化的人为因素。（5分）
（4）针对图中所示地区出现的环境问题，我国采取的主要措施有哪些？（5分）
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读我国西部内陆两地景观示意图，回答以下问题。
小题1:甲地以井为中心在草原上形成沙地，其原因可能是（）A．由于过度开采地下水导致形成地下水漏斗区
B．由于干旱地区地下水含盐量高，使植物不能生存
C．由于风力侵蚀形成风蚀洼地
D．由于有水，以井为中心的地区农牧业活动较多而导致地表植被破坏小题2:在乙地区，可能反映该地区绿洲萎缩的现象是（）
A．地表反射率下降
B．土壤有机质增加，土壤紧实度下降
C．土壤盐碱度升高
D．生物生产能力提高
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过敏反应属于
[ ]
A．体液免疫B．细胞免疫C．自身免疫D．免疫缺陷
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I had never seen sand dunes（沙丘）before. If you go to the seaside in Britain, you may see some small hills of sand, but nothing very impressive. Of course, Africa is home to many beautiful “sandscapes”, but I was in China, so I went to Dunhuang. I had spent my first day looking at the beautiful Mogao caves. Now I wanted to experience something very different. I have been walking in Asia, Europe and America, but nothing prepared me for walking over hills of sand. Whenever I took a step up a hill, my feet would sink into the sand and move backwards. Sometimes it seemed as if I were moving in the wrong direction. I wanted to see the sunset so I had to climb to the top of the highest sand dune. The sun was beating down upon my back as I walked slowly over the sand. Some plants had managed to survive in the dry ground but not many. As I climbed higher, the hills of sand became steeper and my feet started to slip further backwards. I ended up with my hands and knees, crawling （爬行)upwards through the top. I just let go if I would fall the way down. But I refused to give up: inch by inch, I made my way to the top of the sand dune. When I got there I was amazed by what I saw. The sand formed a very sharp point, just like a knife-edge. One side of the dune was bathed in sunshine, the other covered by shade. As I looked into the distance, the same pattern was repeated on all of the hilltops, and the difference between dark and light was beautiful. As the sun began to sink, the shadows grew longer and the light became warm and orange. The wind had come to life and sand was blown against my legs as I walked along the dunes. Soon it was getting dark and I could only just make out the line of footprints that marked my journey to the top of the hill. I slowly made my way down to the bottom, my path lit by the dying sun. 65 The author probably went to climb the sand dunes ____ after he arrived at Dunhuang. A. on the afternoon of the first day B. on the afternoon of the second day C. on the evening of the second day D. on the evening of the first day
Which of the following statements is NOT true？A. Africa has many beautiful sand dunes. B. The author could see nothing but his own footprints on his way back. C. The author had seen some kinds of sand dunes before he visited Dunhuang D. What attracted the author most was that the sand formed a very sharp point.
The author got to the top of the highest hill of sand _________.A. on his hands and knees all the way B. with falls to the bottom many times C. on his hands and knees in the last leg （一段旅程) D. with a few rests all the way
The author mainly wants to tell readers about_________.A. the beautiful sunset B. his experience of climbing the sand hills C. the joy of traveling in nature D. the difficulty of climbing the sand dunes
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阅读下面一首元曲，回答问题。
《双调·沉醉东风》关汉卿咫尺的天南地北，霎时间月缺花飞。手执着饯行杯，眼阁着①别离泪。刚道得声保重将息，痛煞煞②教人舍不得。好去者，望前程万里！
①阁着：含着。②痛煞煞：痛苦到了极点。（1）请说出“咫尺的天南地北，霎时间月缺花飞”一句的含义。 _____________________________（2）本曲运用了哪些人物描写的手法来表现离别的主题的？试举例说明。 _____________________________
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In “Relax, We’ll Be Fine”, columnist David Brooks writes, “the fact is, despite all the problems, America’s future is extremly bright.”
Mr. Brooks acknowledges that “According to recent survey, 60 percent of Americans think the country is heading in the wrong direction. The same percentage believe that the U.S. is in long-term decline. The political system is not functional. A financial crisis looks unavoidable. There are plenty of reasons to be sad.”
But, he writes:
“Demographers（人口学家) predict that over the next 40 years, the U.S. population will increase by an additional 100 million people, to 400 million over all. The population will be determined, hardworking and relatively young. In 2050, only a quarter will be over 60, compared with 31 percent in China and 41 percent in Japan.”
As the rising generation leads an economic recovery, it will also participate in a communal
（of community) one. We are living in a global age of social entrepreneurship（创业精神).
In sum, the U.S. is on the edge of a demographic, economic and social recovery, built on its historic strengths. The U.S. has always been good at destructive change. And it’s always been good at decentralized community-building, too. Surely a country with this much going for it is not going to wait around passively and let a rotten political culture drag it down.
51．In his article Relax, We’ll Be Fine, David Brooks intends to________.
A．encourage Americans to be optimistic about their future
B．give Americans courage to face their financial crisis
C．persuade Americans to live happily and generously
D．inspire Americans to lead an economic recovery
52．There are all the reasons for Americans to be unhappy except____
A．the function-failed political system B．the increasing population
C．the declining economy D．the wrong direction and financial crisis
53．Over the next 40 years, according to David Brooks, Americans will be____
A．more optimistic and humorous B．more pessimistic and stronger
C．more energetic and promising D．more considerate and aggressive
54．In the author’s opinion, America________.
A．has always benefited from wars B．has done well by its political system
C．has contributed a lot to human progress D．has contributed to world’s economy
55．We can learn from the passage that____
A．American political system and culture are backward
B．Americans are not a nation to give in to difficulties
C．Americans are very destructive and aggressive
D．America has been in an economic and social recovery