我想知[[我只想你開心]]英文係咩?我要d未深d!20點(快)

我只想你開心 = I simply/only want you to be happy.
只要你開心, 我... = As long as you are happy, I...

I simply/only want 就是"我只想", 上面那位用戶大致上對, 但 only 位置不對。i.e. I want you to feel happy only (我想你只感覺到快樂。那麼其他感覺呢?). 我建議這句話應改為 "I only want you to feel happy."

I want you to feel happy only.

just有點命令的意思，only比較好。

I just want you feel happy.