stratified medium累: tired; fatigued; weary层: I storey; tier; stratum煤: coal质: nature; character; essence煤质: anthrax; coal grade; coal property; coal quality; coalproperty下载手机词典可随时随地查词查翻译关注微信公众号：chachacidian，回复:累层煤质，即可在微信中查询翻译
