Undocumented
a. 无正式文件的, 无事实证明的
🗣️ 情景例句
Who's buying the drinks?
谁来买酒？
The more a man knows, the less he knows he knows.
懂得越多，就越知道自己懂得不多。
He has tasted the sweets and bitters of life.
他已尝遍了人生的甜酸苦辣。