功率区段 power range
参考答案：反应堆的控制主要依据温度或中子通量密度测量而不是根据周期测量时的反应堆功率范围。
Tom has much difficulty _____Chinese so he often asks me _____ help.[ ]
A. to understand, with
B. understanding, of
C. to understand, for
D. understanding, for
应在什么地方悬挂“禁止合闸，有人工作！”或“禁止合闸，线路有人工作！”的标示牌？
