sine qua non
noun [ S ] formal uk/ˌsɪn.eɪ kwɑː ˈnəʊn/ us/ˌsɪn.eɪ kwɑː ˈnoʊn/
必要条件，必备条件
a necessary condition without which something is not possible
An interest in children is a sine qua non of teaching. 喜欢孩子是从事教育工作的必要条件。
江苏热线英汉汉英双解词典包含207361条英汉翻译词条，涵盖了常用英语单词及词组短语的翻译及用法，是英语学习的必备工具。