Often, a song's title is included in the first line of the chorus. The title may also appear in the last line. Songtitles are often inserted in the chorus to amplify the emotional impact of the song. Generally, a song's chorus will contain the same melody and paroles de chansons as the verses, although it is possible to subvert the meaning of the song. Whether a song is written in a rhyme scheme or not, the chorus is designed to be an upbeat, catchy refrain that summarizes the emotional theme of the song.
Identifying the songtext in a poem can be tricky, especially when comparing verses to chorus. For example, Bob Dylan famously used an ABABCB verse and chorus structure for his song "Tangled Up in Blue" in 1975. However, this structure doesn't always imply that the chorus will be the climax of the song.
One of the best ways to learn to write lyrics is to listen to popular songs. Many of them contain great songtext. Take the time to look through the lyrics of your favorite artists. Not only will you learn about songtext, you'll get a feel for how to write a lyric that captures the emotions of a difficult time or experience.