用兆欧表检查线路绝缘时，与齐纳式安全栅连接导线应（）。 A.短接 B.断开 C.无关

根据音标写单词。    

     A good ['brekf?st]            is import.ant. We can ['i:zili] __         understand it. We have not eaten

['eniθi?]              for about twelve hours by breakfast time. Our bodies need food for ['m?:ni?]            

activities.                                                                                       

     One good breakfast should be rice or bread, an egg, milk and [fru:t]_         . On a cold morning,

a cup of hot  [dri?k]            is necessary. We must get up ['3:li]             to have enough time to eat

breakfast. A good breakfast helps us to [smail]              more easily. It helps us to be more

['frendli]               and also to [w?:k] __         better and play more happily.

柯尔伯格研究道德发展的主要方法是()。

A.自然观察法

B.实验室实验法

C.两难故事法

D.对偶故事法

资金具有时间价值的根本原因是（）。

A.投资和再投资

B.资金能产生利润

C.资金具有增值性

D.市场供求关系的变化

电气设备的高、低压是如何划分的？