为解决单相异步电动机不能启动的问题，在定子上除安装工作绕组外，还应与工作绕组空间相差

原发性免疫缺陷病最为显著的临床特征是（）

A.反复、慢性感染

B.生长发育延迟

C.自身免疫倾向

D.家族集聚发病

E.肿瘤发生几率增高

读“我国人均耕地变化图”(图2-1-32)，完成下列问题。

图2-1-32

(1)从人均耕地变化曲线看，我国的人均耕地面积在日趋_________，这一趋势若不能得到有效的缓和，按1955－1975年的速度发展，大约在2005年，我国人均耕地将趋近于_________。

(2)造成这一现状的主要原因是_________。

(3)我国可以开垦的荒地已经不多了，主要分布在_________和_________等省区，我国土地利用类型中面积最大的是_________。

Once upon a time, there was a large mountainside, where an eagle’s nest rested. The eagle’s nest contained four  36  eagle eggs. One day an earthquake rocked (使震动) the mountain  37  one of the eggs to roll down the mountain,  38  a chicken farm, which was in the valley below. The chickens knew that they must  39  and care for the eagle’s egg, so an old hen   40  to hatch (孵) and raise the large egg.

One day, the egg hatched and a beautiful eagle was born.  41 , however, the eagle was raised to be a(n)  42 . Soon, the eagle believed he was  43 more than a chicken. The eagle loved his home and family, 44  his spirit cried out for more. While playing a game on the farm one day, the eagle looked to the skies above and 45 a group of eagles soaring (高飞) in the skies. “Oh,” the eagle  46 , “I wish I could soar like those birds.” The chickens shouted with  47 , “You cannot soar with those birds. You are a chicken and chickens do not soar.”

The eagle  48  staring at his real family up above, 49  that he could be with them. Each time the eagle would let his  50  be known, he was told it couldn’t be done. That is  51  the eagle learned to believe. Slowly, the eagle  52  dreaming and continued to live his life like a chicken.  53  , after a long life as a chicken, the eagle  54 .

You become what you believe you are; so if you ever dream to become an eagle, 55 your dreams, not the words of a chicken.

监狱作为国家机器的重要组成部分是（）。

A、阶级矛盾不可调和的产物和表现

B、随着国家产生而产生

C、掌握国家 * * 的阶级进行统治的工具

D、人民民主专政的工具

粘度分为动力粘度与运动粘度。