题目内容
符合（）情况之一时，宜采用绕线转子异步电动机。 A．机械对起动、调速及制动无特殊要求时，应采用笼型异步电动机，但功率较大且连续工作的机械，当在技术经济上合理时，宜采用同步电动机 B．重载起动的机械，选用笼型电动机不能满足起动要求或加大功率不合理时 C．调速范围不大的机械，且低速运行时间较短时 D．机械对起动、调速及制动有特殊要求时，电动机类型及其调速方式应根据技术经济比较确定。在交流、电动机不能满足机械要求的特性时，宜采用直流电动机；交流电源消失后必须工作的应急机组，也可采用直流电动机
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Section B
Directions: In this section, you will hear 3 short passages. At the end of each passage, you will hear some questions. Both the passage and the questions will be spoken only once. After you hear a question, you must choose the best answer from the four choices marked A, B, C and D.
(31)
听力原文：F: Can you pass me a dish, darling？
M: Here you are. This dish is clean. I washed it just now.
What is the relationship between the two speakers？
输血时，需要有几名医护人员核对患者情况，确认配血报告，核对血液后，进行输血（）
Changes in residence and jobs place a tremendous amount of stress and pressure【B1】people【B2】they try to adjust themselves to new people and places. Yet short-lasting relationships are not【B3】only to people and places. Objects move in and out of our lives at an astonishing rate. America, the "consumer society", has also been【B4】the name "the throw away society". Every year we throw away【B5】quantities of bottles, cans, paper, and on and on, buildings are pulled【B6】around us, and new ones take their place; they are cheaper to replace than to repair.【B7】every major change, our places feel【B8】familiar. Our lives become filled【B9】a sense of impermanence and uncertainty.
The rate at which new and sometimes contradictory information comes at us【B10】contributes to our feelings of instability and transience. It's estimated that 90 percent of all scientists who ever lived are【B11】today. New scientific discoveries are being made every day of the week,【B12】unlike in other ages, new ideas are quickly applied in practical ways. The【B13】of new technology on our lives is felt almost immediately.
As we look【B14】on history, we think in terms of large periods of time, from the ten thousand years of the agricultural revolution to the three hundred years of the industrial【B15】. Today time【B16】like it's speeding up. We no longer【B17】to think of change in terms of centuries,【B18】in terms of【B19】, the 1960's, 1970% and 1980's. The day may come【B20】we will think of great historical change in terms of years, even months.
【B1】
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