Indispensability
出国 Abroadn. 不可缺少, 责无旁贷
✅ 同义词
🗣️ 情景例句
Yes, ice cream.
对 ，冰淇淋。
One cannot put back the clock.
光阴一去不复返。
It's a pleasure. What time is it by your watch, please?
不客气。请问，你的表几点了？