sin qua non
英 [sɪn kweɪ ˈnəʊn]
美 [sɪn kweɪ ˈnoʊn]
【法】绝对必需，必要条件，不可缺
双语例句
- The experiment of building materials is a link sin qua non in construction. Through experiment engineers can appraise the raw material, intermediate product and structure component scientifically and the experiment is a basic work to ensure the quality of architecture and civil engineering.
建筑材料试验是建筑工程建设中不可缺少的一个环节，通过试验能科学地鉴定建筑物使用的原材料、半成品和结构构件的质量，是保证建筑工程质量的基础环节。