Tau.
[医] 寿命(放射性物质)
🗣️ 情景例句
God helps those who help themselves.
天助自助者。
You cannot make a silk purse out of a sow's ear.
猪耳朵做不成丝钱包；巧妇难为无米之炊。
'But I'm still having breakfast,' I said.
“但我还在吃早饭，”我说。