短語(yǔ)詞組短語(yǔ)protection n course 保護(hù)層International environmental protection development course 國(guó)際環(huán)境保護(hù)發(fā)展歷程stabilized protection course 穩(wěn)定保護(hù)層Food Protection Course 食物保護(hù)課程fire protection course 防火課程steel bar protection course 鋼筋保護(hù)層reinforced protection course 鋼筋保護(hù)層frost protection course 防凍層loose protection course 松散保護(hù)層 返回 protection course