问题
填空题
JT-C系列机车信号电源系统具有()安全点灯电源。
答案
参考答案:动态方波控制
JT-C系列机车信号电源系统具有()安全点灯电源。
参考答案:动态方波控制
从方框中选出五个合适的句子补全对话。 | |
Alice: 1. Dong: Did you smell smoke? Alice: 2. Dong: Where was she? Alice: She was playing in the gym. Dong: 3. Alice: He was eating lunch in the cafeteria. 4. Dong: When the fire started, I was talking on the telephone. Alice: What did you do? Dong: 5. Alice: Good for you! |