Let’s say you want to write a sonnet. This means you have 14 lines, typically written in iambic pentameter, and separated into an octave of eight lines (or two quatrains that sum to eight) as well as a sestet, or a six-line stanza. And you then choose a rhyme scheme. There’s, for example, the Shakespeare approach: ABABCDCD EFEFGG. Or you might opt for the Petrarchan sonnet: ABBAABBA CDCDCD.
Or let’s say you’re feeling somewhat more adventurous and decide to pen a villanelle. Here you are going to write five three-line stanzas and end with a quatrain. However, the first and third lines of the first stanza are alternatively repeated in the subsequent stanzas. The consequent rhyme scheme is: ABA ABA ABA ABA ABA ABAA.
Or, frustrated with either of those, go for a haiku. This is certainly simpler: three lines with a combined 17 syllables, with five in the first and third and seven in the middle.
(Writing a haiku/can cause a feeling of calm/as others frustrate)
Regardless of which form you follow, assuming that you’re writing in English, there are some 470,000 words that you can use.
However, if you’re opting for the sonnet or the villanelle, there are a few more challenges, in that there are several words in English that don’t rhyme. Yes, orange. But the colors purple and silver don’t have rhymes, either. Wolf and walrus. And many others.
So there are restrictions, or boundaries, that are necessary in order to create something within a particular form or genre. Things can be done differently (Shakespeare published 154 sonnets), but in order to be in a particular form there are things that must be there.
Which brings me, in a roundabout way, to the lawsuit brought by the heirs of Ed Townsend against Ed Sheeran in which it was claimed that there was a copywrite violation with Sheeran using chords and rhythms from “Let’s Get It On” in “Thinking Out Loud.”