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带保险丝插座
铝丝代替保险丝 插座起火人烧死
铝丝代替保险丝 插座起火人烧死
铝丝代替保险丝 插座起火人烧死
开关和保险丝
开关和保险丝 An electric switch is often on a wall near the door of a room. Two wires lead to the lamp in the room. The switch is fixed in one of them. The switch can cause a break in this wire, and then the light goes. The switch can also join the two parts of the wire again, then we get a light. Switch can control many different things. Small switches control lamps and radio sets because th