若开关空喇叭嘴未装金属垫圈（有挡板）则该开关属（）。
A、失爆
B、不完好
C、完好设备
参考答案：B
— It is kind the doctors to devote all the time he had to for the patients.
— I think so, they are so great.
A．for, care
B．of, care
C．of, caring
D．for caring
什么是在线应用？
