Quadriennum utile
[法] 四年有效期
🧩 词语组成解析
a. 有用的；有益的
🗣️ 情景例句
I can't believe this is really happening!
我不敢相信这一切真的发生了
I can't help it, sir.
我也无能为力，先生。
That one is only 90 fen. That's cheap.
那支笔只有九毛钱，很便宜。