Tracer technique
[化] 示踪技术
🧩 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 look very young. How old are you?
你看起来真年轻， 你多大了？
What do you want?
你到底想怎样？
I have a surprise for you.
我有一个意想不到的东西给你看。