Radioactive standard
[化] 放射性标准源
🧩 词语组成解析
standard
['stændɚd]
n. 标准，规格;旗，军旗;度量衡标准;直立支柱;
adj. 标准的，合格的;普遍的，一般的;公认为优秀的;
🗣️ 情景例句
What are you working on?
你在干什么？
He likes playing the organ.
他喜欢拉风琴。
It was carrying some large bags of rice. Suddenly one of the bags fell off the truck.
它运载着大包大包的米。突然一袋米从卡车上掉了下来。