Argument by analogy may be thought of as argument from the particular to particular. An argument by analogy may use a particular truth in a premise to argue towards a similar particular truth in the conclusion.
A Rhyming Couplet is two line of the same length that rhyme and complete one thought. There is no limit to the length of the lines. Rhyming words are words that sound the same when spoken, they don't necessarily have to be spelt the same.
Metaphysical poems are lyric poems. They are brief but intense meditations, characterized by striking use of wit, irony and wordplay. Beneath the formal structure (of rhyme, metre and stanza) is the underlying (and often hardly less formal) structure of the poem's argument.