The formula is because of the structure of an authentic song, particularly for put, funk, or rock songs. The structure is simple and goes like this:
1) the introduction which is normally 4 to eight bars in length before the verse; two) the very first saying; 3) either the second verse, or: 4) the chorus, subsequent; 5) a single; 6) the link; 7) repeat a verse; 
replicate chorus as soon as or as several times as you like, and lastly; 9) the outro or even the ending. The refrain is also called “the hook” and could be repeated in the conclusion while the recording ends.
Singing lyrics of songs you like will bring you simple pleasure, a past time that you will enjoy.
