什么是产褥期抑郁症?
参考答案:产褥期抑郁症是指产后6周内首次发病(既往无精神障碍史),以抑郁、悲伤、沮丧、哭泣、易怒、烦躁、失眠等一系列症状为特点的精神异常。
They were all asleep. _____ of them heard the sound. [ ]
A. Both
B. All
C. None
D. Neither
电压互感器的中性点引出线上不应装设熔断器