问题
单项选择题
电力系统正常运行时，A、B、C三相电压相邻相序之间差（）度。
A.0
B.60
C.90
D.120
答案
参考答案：D
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电力系统正常运行时，A、B、C三相电压相邻相序之间差（）度。
A.0
B.60
C.90
D.120
参考答案：D
完形填空(共20小题,每小题1.5分, 满分30分) I’ll never forget May 12, 2008, we were having classes at Beichuan Middle School , Sichuan Province, when a huge 36 hit the area. At about 2:28 p.m, our 37 , Mr.Wang, was teaching us singing on the fourth floor on the teaching building. 38 we felt the building shaking violently. It was an earthquake! Our building starting to 39 . It was too late to rush out to the 40 . We were told to hide under the desks. 41 later, the whole building fell down. We were 42 in ruins. We couldn’t move at all. No one could really imagine at that split second, how much pain we had 43 or how desperate(绝望的) we felt as we waited to be 44 . I heard Mr. Wang calling our names again and again… . Hours later, some people came to rescue and 45 of us were saved. Later, I 46 this huge earthquake scaled 8.0 magnitude. It hit several provinces, including Sichuan, Gansu and Shanxi. So far it has 47 more than 80,000 and injured 360,000. My hometown ----Beichuan was 48 the worst-hit areas. Our school , which was 49 filled with vigor(活力) and laughter, was a dead valley. Words after such a 50 could appear nothing but empty and pointless. So many people’s lives were taken away, so much 51 was done and the whole city was 52 . Beichuan has become a history. Now , some of my classmates and I were 53 to study in a middle school in Jiangsu Province. I still 54 dreaming and still strive for a better future: to make our homes beautiful yet 55 . May victims rest in peace. May survivors live to be stronger.
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