In many verse–chorus songs, verses develop the story or situation with changing words, while the chorus returns to a familiar musical and lyrical centre. Repetition makes that return recognisable; contrast gives it somewhere to return from.
A song may also include an introduction, a bridge or other sections. Listening for form means noticing patterns and functions rather than forcing every song into one rigid sequence. Ask what changes, what returns and which section feels like the main point of arrival.