Rhyme Scheme of Sonnet 116

The usual way to note the pattern of rhyme at the ends of poetic lines is to use different letters to represent different values in sound, as shown below with the help of color coding.

Let me not to the marriage of true minds

Admit impediments. Love is not love

Which alters when it alterations finds,

Or bends with the remover to remove.

Oh no! It is an ever fixed mark

That looks on tempests and is never shaken.

It is the star to every wandering bark,

Whose worth's unknown, although his height be taken.

Love's not Time's fool, though rosy lips and cheeks

Within his bending sickle's compass come.

Love alters not with his brief hours and weeks,

But bears it out even to the edge of doom.

If this be error and upon me proved,

I never writ, nor no man ever loved.

Let "a" represent the first vowel sound at the end of a line and the consonants that go with it (inds in line 1). When that sound repeats (in line 3) it is again listed as "a" in charting the alternating pattern of rhyme. (Note the single letters to the right of each line of the poem.) The new sound ending line 2 = b; the ending of line 4 looks like it rhymes (called "sight rhyme") even though the sound match is imperfect in modern English. These imperfect rhymes are marked in red, even the two f's near the end that aren't even spelled the same (but they are both alternates of the short /o/ sound).

So? So look for places of emphasis and for variations. English sonnets are said to be made of 3 quatrains and a couplet. That is, lines 1-4, 5-8, 9-12 group together, and the last two lines group together.

What groups them? The quatrains use 2 rhymes each in alternating lines. The first quatrain's rhymes are marked in green and red, the second quatrain's in orange and white, the third in aqua and the red for imperfect rhymes. Red, again, marks the imperfect rhyme of the ending couplet.

Where do the sentences end? In this sonnet, they end halfway through or at the end of each quatrain. Since the couplet varies the rhyming pattern of the first twelve lines, it stands out; it also stands out because it's the end, the climax emotionally for the poem.

So? So the ends of lines 4, 8, 12, and 14 should be louder than other syllables--and filled with relatively more important words. Certainly, "doom" (death) and "loved" are crucial to this sonnet's theme.

In short, someone crafting a sonnet will take advantage of typical places of emphasis--like the end of a rhyme, the end of a sentence, and the end of the poem--by putting major hints to the theme or idea of the poem in those positions. The rhymes in these positions heighten the emphasis.