Asymmetrical--describes a period in which the phrases differ
in length.
Cadential extension--the prolongation or delay of the cadence
by the addition of material beyond the point at which the cadence is
expected.
Contrasting--describes a period in which the musical content of
the phrases differs.
Double period--a periodic structure in which the
antecedent-consequent relationship is fulfilled by pairs of
phrases.
Elision--the (melodic) connection of two phrases in such a way
that the cadential point of the first coincides with the beginning of
the second.
Interpolation--the lengthening of the repetition of a phrase by
the insertion of material not heard in the original phrase.
Link--material that appears between the end of one phrase and
the beginning of the next, but belongs to neither.
Modulating--describes a period in which modulation occurs in
the consequent phrase(s).
Parallel--describes a period in which the musical content of
the phrases is the same.
Symmetrical--describes a period in which the phrases are the
same length.
