The poem has fourteen lines, divided into three quatrains (stanzas) of four lines each followed by a concluding couplet of two lines –
Quatrain (stanza) one introduces the topic, or thought to be explored
Quatrain two develops the topic
Quatrain three further develops the topic
The couplet sums things up.
The rhythm in each line is comprised of 5 beats, called iambic pentameter.
So it basically goes like this – ta DUM ta DUM ta DUM ta DUM ta DUM
Eg. the first line from Shakespeare’s sonnet 18, shows us the way,
“Shall I compare thee to a summer’s day”
The bolded parts in the line shows us where the down beat falls; in other words they are the ‘DUM’s’ in the ‘ta DUM’s’.
Considering the sound of the word at the end of each line,
the rhyme scheme of quatrain one is – abab
quatrain two is – cdcd
quatrain three is – efef
the couplet – gg