Radioactive tracer
[化] 放射性示踪剂
🧩 词语组成解析
tracer
['treisə]
n. 追踪者，描图者，（铁笔等）绘图工具;
🗣️ 情景例句
You were right, Philip.
你说对了。 Philip。
To facilitate carrying, rope or metal handles are indispensable and should be fixed to the boxes.
为便于搬运，绳子或铁把手不可缺少，并将其固定在箱子上。
It had broken down the previous summer, and though I promised to repair it, I had never got round to it.
那台割草机去年夏天就坏了，尽管我答应修，但一直没抽出时间，