1. Quatrains and Couplets: A Shakespearean sonnet consists of 14 lines, divided into four quatrains (four-line stanzas) and a final rhyming couplet (two-line stanza).
2. Iambic Pentameter: Each line of a Shakespearean sonnet should be written in iambic pentameter. This means that each line is composed of ten syllables, with alternating unstressed and stressed syllables.
3. Rhyme Scheme: The quatrains follow an ABAB CDCD rhyme scheme, while the final couplet rhymes with an EE rhyme scheme. Here's an example:
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When in disgrace with fortune and men's eyes, (A)
I all alone beweep my outcast state, (B)
And trouble deaf heaven with my bootless cries, (A)
And look upon myself and curse my fate, (B)
Wishing me like to one more rich in hope, (C)
Featured like him, like him with friends possessed, (D)
Desiring this man's art and that man's scope, (C)
With what I most enjoy contented least; (D)
Yet in these thoughts myself almost despising, (E)
Haply I think on thee, and then my state, (E)
Like to the lark at break of day arising (F)
From sullen earth sings hymns at heaven's gate; (G)
For thy sweet love remember'd such wealth brings (F)
That then I scorn to change my state with kings. (G)
```
4. Theme: Shakespearean sonnets often explore themes of love, loss, time, beauty, nature, and mortality.
5. Volta: The third quatrain (lines 9-12) usually features a volta or a "turn" in the poem, where the speaker's tone or perspective shifts. This shift often leads to a contrasting thought or resolution in the final couplet.
By adhering to these rules, Shakespearean sonnets create a distinct poetic structure that adds to their musicality, emotional depth, and memorable quality.