Ost
abbr. 科学技术局（Office of Science and Technology）
🗣️ 情景例句
First round's on me.
第一轮我请客。
It's faster but more expensive to ship goods by air.
空运较快但运费较高。
Of course. Good luck. Have a good trip.
一定。祝你好运。旅途愉快！