noun 下载 🔗分享 车辕，辕木。 One of the two long pieces of wood, extending before a vehicle, between which a horse is hitched; a shaft. Examples : "The farmer carefully attached the horse to the wagon's thills. " 农夫小心地把马套在马车的辕木上。 vehicle machine part 与AI对话词汇游戏阅读练习
noun 下载 🔗分享 底煤，煤底。 The shallow stratum of underclay that lies under a seam of coal; the bottom of a coal-seam. Examples : "The miners carefully scraped away the last of the coal seam, being cautious not to damage the soft thills underneath. " 矿工们小心翼翼地刮去最后一层煤层，谨慎地不要损坏下面柔软的底煤。 geology material substance industry 与AI对话词汇游戏阅读练习
