“optional”的概念、定义、翻译、参考文献-科学参考

单词	optional
释义	optional 选购的任选的任意的任意选择的随意随意的可选择不是必需的
随便看	permanent tooth eruption permanent transfer permanent twist permanent vegetation permanent virtual circuit permanent virtual circuit (PVC) permanent wave permanent weight permanent white permanent wilting permanent work permanent working capital permanganate permanganate demand permanganate index permanganate method permanganate number permanganic acid permanganimetric method Permanite Permant perma-split capacity motor permasyn motor permatron permature birth living child

科学参考收录了1248194条科技类词条，基本涵盖了常见科技类参考文献及英语词汇的翻译，是科学学习和研究的有利工具。