回答

・Congratulations on your engagement!
・Congrats on your engagement!

「恭喜你們訂婚」的英語有 Congratulations on your engagement! 或 Congrats on your engagement! 兩個表達方式。

Congratulations on your engagement! Are you planning on having a wedding?
（恭喜你們訂婚！有打算舉辦婚禮嗎？）

Congrats on your engagement! I'm so jealous you.
（恭喜你們訂婚！我好羨慕你。）

有幫助｜0