外侨形式的主接线适用于( )
A．(A) 出线线路较长，主变压器操作较少的电厂
B．(B) 出线线路较长，主变压器操作较多的电厂
C．(C) 出线线路较短，主变压器操作较多的电厂
D．(D) 出线线路较短，主变压器操作较少的电厂
参考答案：C
解析：及本组的变压器均停止工作。因此，当线路较长，发生故障概率较大，且变压器不需经常切除时，以采用内桥接线为宜；反之宜采用外桥接线。当系统有穿越功率流经本厂(如：双回路出线均接入环彤电网)时，也应采用外桥接线。为检修桥断路器TQF不致引起系统开环，
| 根据对话内容从方框内所给的选项中选出最佳答案，使对话完整,符合逻辑，句意通顺，注意有多余选项。 | |
| |
| A: You must be really excited about leaving for America tomorrow, Li Ping! B: Yeah. 1 A: Nervous about what? B: I don't know many of the customs and manners in the USA. 2 A: Sure. B: 3 A: Well, it's important to be on time when you're invited for dinner. 4 Americans expect their guests to be on time. B: Then how long may I stay there? A: 5 Or you seem to have come only for the meal. When your friends seem to be getting tired and running out of things, it's time to leave. The next day, call or write a thank-you note to say how much you enjoyed the evening. |