以下是快樂日的歌詞：
Today is the day of happiness,
Let's dance and sing with joy.
Open your heart, let it be free,
Today is the day of happiness.
Laughter and joy fill the air,
Happiness is all around.
No worries, no troubles today,
Just let yourself be happy.
Smile and be kind to others,
Spread the happiness far and wide.
Today is the day of happiness,
Let's make it a great day!
這是一首歡快的歌曲，歌詞中充滿了對快樂的嚮往和追求，鼓勵人們打開心扉，享受生活，擁抱快樂。歌曲旋律簡單，容易上口，適合在各種場合播放，讓人們感受到快樂的力量。