✔ 最佳答案
Cloud 9 = very happy (very informal English) 極開心, 開心死, 猶如上了天堂 (非一般用語)
Example:
He's been on cloud nine ever since she agreed to marry him.
You are on cloud 9 ~ It implies that you are having a heavenly experience, blissfully happy as if you were up on a special cloud.
Quote from Urban Dictionary:
When people are extremely happy they sometimes mention that they 'feel like they are on Cloud 9', meaning that they essentially feel like they are in heaven.
“Cloud nine” is also a song ~ sung by the rock group "Temptations" in 1968. It reached Number 6 on the billboard .