直流配电屏是()和()直流供电系统中整流器和蓄电池组向通信设备供电的电源设备。
参考答案:连接;转换
at the end of;by the end of;in the end
1. The Reads live in the house ________ the street.
2. ________ they had to leave their home.
3. They had kicked three goals ________ the match.
采用埋设固定的横担、支架及螺栓、拉环的埋设端应制成()
A.铁脚
B.燕尾
C.锚具
D.圆弧