The main melody and submelody mentioned here refers to polyphonic counterpoint. The so-called main melody and submelody are two melody parts with independent melody that are performed at the same time. The submelody uses counterpoint fugue according to the main melody. To write is one of the skills of composition. Famous polyphonic music such as canon. The verses and choruses in pop music are the concept of paragraphs and are related to the form of the music. The two are completely different concepts.