过滤式自救器的使用方法包括()。
A、取下保护罩、拉开封条
B、拨开外壳上盖
C、取出药罐
D、戴上头戴,用鼻夹夹住鼻子,咬住口具进行呼吸
参考答案:A, B, C, D
—I can’t get on with some of my classmates. They just leave me in the cold.
—______ But what’s the reason?
A.Sorry to hear that.
B.How about that?
C.Don’t mention it.
D.Never give up.
氧气软管为红色,乙炔软管未()色,严禁错连接。