The sonnets are almost all constructed of three quatrains (four-line stanzas) followed by a final couplet. The sonnets are composed in iambic pentameter, the meter used in Shakespeare's plays.
The rhyme scheme is ABAB CDCD EFEF GG. Sonnets using this scheme are known as Shakespearean sonnets, or English sonnets, or Elizabethan sonnets. Often, at the beginning of the third quatrain occurs the volta ("turn"), where of the poem shifts, and the poet expresses a turn of thought.