短语词组短语coal thawing pit 煤的解冻库non -coal open pit 非煤露天矿山water in coal pit 矿井水small -coal pit 小煤窑ancient coal pit 古煤窑Huachu coal pit 化处矿井Huojitu excavated coal pit 活鸡兔采煤塌陷区coal pit a surname 煤坑coal pit waste water 矿井水 返回 coal pit