Like summer's always gonna turn into fall Like when you don't know the words but you still sing along Like how when there's thunder, there's lightning too How the trees are green and the sky is blue Nothing's gonna change, you and I are inevitable You didn't even have to say hello For me to love you till the day I go I didn't believe in love at first sight Then you walked in and I saw my whole life Didn't even have to say hello 'Cause when you know, you know Shooting stars, fireworks, and desert skies ('Cause when you know, you know) All my life, I waited for the Sun to shine ('Cause when you know, you know) Fall in love overnight Sudden rush, butterflies Oh, nothing's gonna change, you and I are inevitable You didn't even have to say hello For me to love you till the day I go I didn't believe in love at first sight Then you walked in and I saw my whole life Didn't even have to say hello 'Cause when you know, you know 'Cause when you know, you know You didn't even have to say hello Didn't even have to say hello 'Cause when you know, you know