Radioindicator
[化] 放射性指示剂
🗣️ 情景例句
What was your best subject in college?
大学时你哪门功课最好？
Why are you standing behind the door?
你为什么站在门后？
If they knew how difficult it was to drill through the hard rock, they would lose heart.
如果他们知道了钻透那坚硬的岩石有多么困难，他们会丧失信心的。