Exchanging
v. 交换；兑换；交流（exchange的ing形式）
✅ 同义词
🗣️ 情景例句
Hello.
哈喽。
Purse
皮包
and then there are three thousand million other Milky Ways, or galaxies, in the universe.
况且在宇宙中还有30亿个天河，即银河系。