The R.ape of the Lock is a mock-heroic narrative poem written by Alexander Pope, using the heroic couplet. A couplet refers to a stanza consisting of two lines only, and heroic means that each of these two lines is written using rhyming iambic pentameters. Iamb means that an unstressed syllable is followed by a stressed one. Pentameter means that there are 5 meters in one line (penta = 5), and given that one meter equals two syllables, pentameter is a line consisting of 10 syllables.
