他正在用一把大镰刀割草.He's cutting grass with a scythe.他正忙着干活, 在磨一把长柄大镰刀的刃儿.He was very busy, putting an edge on a scythe.长柄大镰刀嗖嗖地来回挥动.Scythes swished to and fro....
绿片岩相以下的动力变质作用是矿化富集的条件.Dynamical metamorphism under greenschist facies is the condition of mineralizing enrichment.大水沟独立碲矿床的直接赋矿围岩为低绿片岩相变质岩.The host rocks of Dashuigou independent tellurium ore deposit are mainly green sc...