A:更换灯泡时、搬动电器前应断开电源开关
B:不弄湿用电器,不损坏绝缘层
C:可以接触低压带电体,但不能靠近高压带电体
D:保险装置、插座、导线、家用电器等达到使用寿命应及时更换
2011年暑假期间,有甲、乙、丙、丁四位同学分别到亚洲四个不同的地点旅游。回校后他们各自描绘了自己的所见所闻,其中描绘不正确的是( )
When the room_____by electricity, we can see the_____ candles on students’ desks sending off heavy smoke.( )
细胞与外界环境进行物质交换的媒介是____ .
— How much are the two pairs of trousers?— They are not expensive. I think one hundred dollars ______ enough.