Operational maintenance
[计] 运行维护
🧩 词语组成解析
🗣️ 情景例句
What's your idea of price?
价格如何？
The wise man knows he knows nothing,the fool thinks the knows all.
聪明人自认一无所知，愚笨人自负无所不晓。
Suddenly, they heard a voice behind them.
突然他们听到身后有声音。