Happy Day的英文歌詞如下：
Verse 1:
I'm feeling good today
Everything's the same
I'm not gonna let it get me down
It's gonna be a happy day
Chorus:
Happy day, happy day
Gonna make it through today
Happy day, happy day
Gonna be the best day of my life
Verse 2:
Got a smile on my face
A spring in my step
Gonna make the most of every moment
It's gonna be a happy day
Chorus:
Happy day, happy day
Gonna make it through today
Happy day, happy day
Gonna be the best day of my life
Bridge:
Everybody needs a little bit of happiness
So let's enjoy this day and make it unforgettable
Let's make the most of every moment that we have together
It's gonna be a happy day for me and you
Chorus:
Happy day, happy day
Gonna make it through today
Happy day, happy day
Gonna be the best day of my life (x2)
以上歌詞為 Happy Day 的基本內容，僅供參考。