下图中甲处可能是
A．背斜
B．向斜
C．地垒
D．地堑
答案：C
本题考查地质构造与构造地貌。地质构造分为：皱褶（背斜、向斜）和断层。皱褶形成的地形一般为：背斜成山；向斜成谷。倒置的地形：背斜顶部受到张力被侵蚀成谷地；向斜槽部受挤压岩性坚硬不易被侵蚀反而成山岭。断层上升岩块成山岭或高地（华山、庐山、泰山），下降岩块（地堑）成谷地或低地（渭河平原、汾河谷地）。图中甲处为断层上升形成的地垒。所以本题选择C选项。
Why are you always tired, do you know? First, if(如果) we can’t 31 well, we will(将) be tired. But we are often too 32 . We can’t finish our work in the day 33 we have to do it at night. We go to bed 34 and we get up early in the morning for school or work. Most people need at least(至少) eight 35 or some more. If we sleep for only five or six hours a night, we will be tired. Second, when we are ill, we will be tired. But we don’t know we are ill. So if you are always tired, maybe you are not so 36 . You’d better go to see a 37 . Third, maybe you eat 38 food, like hamburgers, meat, chocolate or coffee. If you are ill and tired after eating some food, please don’t eat it 39 to see if you are well. At last, if the air around you isn’t nice and clean, you will feel tired. So please open your windows often or go out for a walk and you will feel 40 .
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