primary source material

基本解释

Source material: Primary source for all four librettos is Schott's 1899 vocal scores (republished in the United States by Schirmer in 1904).
资料来源：四个版本都来源于1899年Schott出版的歌谱（该歌谱1904年在美国由Schirmer再版）。
One material source of diamond is primary diamond mines and ancient placer in the ancient Yi River upstream in Shandong, the other is the primary diamond mine which may exist in this area.
金刚石的物质来源一是古沂河上游山东的金刚石原生矿和古砂矿，二是本区的可能存在的金刚石原生矿。
After the timeline was completed, the students were arranged in groups, and each group did a critical analysis of primary-source material, focusing on the efforts each side made to avoid the war.
经过时间完成了，学生们被安排在组，每组做了批判性分析的主要源材料，着眼于努力，每一方，以避免战争。

"We've always had the philosophy that we're the primary source for this material, " he says.
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