Parallel patterns are the echoing of a syntactic pattern in the proximate segments of the text with different or partially different lexical components. The parallel segments become correlated by way of contrast, resemblance, analogy, gradation,etc. This very effective means of semantic cohesion and aesthetic arrangement has been a favourite rhetorical figure since ancient times, and has been used in English literature since the earliest period.
Parallel patterning can be complete and incomplete. An ideal case of parallel patterns satisfies the following three requirements:
(1) the members of the reiterated patterns should have identical syntactic functions;
(2) the members of the reiterated patterns should be equal in number ;
(3) there should be identical word order in the reiterated patterns .
When all the three reqirements are met the parallelism of patterns is complete. Very often, however, there is a partial breach of the three requirements and the repetition of patterning is incomplete:
One of the typical cases of incomplete repetition of syntactic patterns is lack of coincidence in syntactic functions.
Lack of coincidence in the word order is known as chiasmus' or reversed syntactic repetition, by which the order of the words in the first pattern is reversed in the second. In other words, chiasmus is a balanced double utterance the second part of which is the reversed image of the first:
Down dropt the breeze, the sails dropt down.(Coleridge)
Depending on the position of identical syntactic parts in parallel pattens, incomplete syntactic repetition can be further classified into syntactic anaphora, syntactic epistrophe and framing.