夏季绿洲的最高气温显著低于其毗邻的沙漠、戈壁，水分的蒸发量也明显较小，非常有利于植物的生长。绿洲与周边沙漠、戈壁的这种气候差异，被称为“冷岛效应”。据此完成下列各题。
“冷岛效应”的形成原因是由于绿洲与沙漠、戈壁之间（）
A、大气环流的差异
B、热力性质的差异
C、太阳辐射的差异
D、距海远近的差异
参考答案：B
解析：
根据材料，“冷岛效应”的形成原因是由于绿洲与沙漠、戈壁之间热力性质的差异，B对。大气环流、太阳辐射的差异、距海远近的差异不是主要原因，A、C、D错。
【点评】区域自然地理环境特征及成因，自然地理环境的特征。
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| Do you like to go camping (野营)? Do you know how to start a fire? If you don't know how to start a fire, you 1 your food, and can't sit by the side of a fire, and can't keep yourselves 2 . Long, long ago people 3 how to start fires. They probably started fires from lightning (闪电). But they had to 4 the lightning fire burning, for there was 5 to start it 6 . Later people learned how to start fires. They 7 out hitting two pieces of stone (石头) together could make a spark (火光).The spark could set 8 on fire (set…on fire 使…… 燃烧). They could start this kind of fire again if it went out (熄火). Then people also learned to make a fire by rubbing (摩擦) two sticks together. They made a hole (洞) on a large stick and put the 9 stick into the hole. And then they turned the stick again and again. 10 a few minutes they started a fire. About two hundred years 11 , people began to 12 matches (火柴). One early match looked 13 the match we use today. The match gave people a 14 way to start fires. Today people are 15 finding new ways to start fires. One of the new ways to start a fire is to use an electric fire starter (电子打火器). Now you can 16 matches and electric fire starter at 17 . Of course an electric fire starter is more expensive than 18 , 19 it is useful. After people learned to make fires, their lives became 20 . | ||||
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