何谓电机温升？

下列物质的性质中，属于化学性质的是[ ]

A．木炭是黑色固体

B．碳酸钠粉末易溶于水

C．镁条能在空气中剧烈燃烧

D．二氧化硫有刺激性气味

阅读理解

     When friends come to visit us in the evening, they spend their time telling us they are in a hurry and

looking at their watches. It isn't that our friends are all very busy, it is just that we haven't got a television.

People think that we are very strange. "But what do you do in the evening?", they are always asking. The

answer is very simple. Both my wife and I have hobbies. We certainly don’t spend our evenings staring at

the walls. My wife enjoys cooking and painting and often attends evening classes in foreign languages.

This is particularly useful as we often go abroad for our holidays. I collect stamps and I'm always busy

with my collection. Both of us enjoy listening to the music and playing chess together. 

     Sometimes there are power cuts and we have no electricity in the house. This does not worry us, we

just light candles and carry on with what we were doing before. Our friends, however, are lost—no

television! —So they don't know what to do. On such evenings our house is very full—they all come to

us. They all have a good time. Instead of sitting in silence in front of the television, everybody talks and

plays games.

1. The couple have not got a television, because     .

A. they are not rich enough          

B. they are strange people

C. they enjoy spending evenings in their own ways

D. they don't know what to do when there are power cuts

2. Both of them are interested in     .

A. learning languages  

B. traveling  

C. staying home alone              

D. watching people play games

3.  At night when there is no electricity, the couple       .

A. have to stare at the walls  

B. can do nothing but sit in silence

C. will have many visitors    

D. have to go out for candles

4. The best title for this passage is _____.

A. Why Do We Need a Television?

B. Candle! But No Electricity!

C. Different Friends, Different Hobbies.

D. We Go Without Televisions!

操作"患者仰卧，肩外展约50°并内旋。治疗者外侧手托住上臂远端及肘部，内侧手四指放在腋窝下肱骨头内侧，拇指放在腋前，向外侧持续推肱骨，然后放松，重复3～5次"属于（）

A.分离牵引肩关节

B.前后向滑动肩关节

C.后前向滑动肩关节

D.前屈向足侧滑动肩关节

E.外展向足侧滑动肩关节

脑脊液外观浑浊，WBC>1000×10⁶/L，N90%，蛋白质增高，糖及氯化物降低（）

A.流行性脑脊髓膜炎

B.流行性乙型脑炎

C.结核性脑膜炎

D.病毒性脑膜炎

E.中毒性菌痢

精装书芯压平的作用是什么？