After setting, the surfaces of the specimens are ground down using carborundum and alumina.凝固之后, 样品表面连续用金钢砂或氧化铝磨平.The grinding block made of carborundum abrasive, is very hard and sharp.磨光机磨块采用金刚石磨料制成, 硬度极高,磨削锋利.We repai...
为什么她再三地做那个实验?Why did she do that experiment once and again?我们再三地讨论, 最后达成协议.We discussed it again and again, and then we saw the light.我再三地请求上帝给予指引.And I repeatedly asked God for direction....