Warning: file_put_contents(/home/www/wwwroot/ndsq.cn/cache/e705e330fe6e4858205951f631ae7493.txt): failed to open stream: No space left on device in /home/www/wwwroot/ndsq.cn/index.php on line 55 fundamental unit英英字典_fundamental unit剑桥英语解释_fundamental unit柯林斯英文解释_开心英文字典_柠咚词
1. N one of a set of unrelated units that form the basis of a system of units. For example, the metre, kilogram, and second are fundamental units of the SI system 基本单位; 如：米、千克和秒是国际单位制系统的基本单位