Phrases and Periods

Tonal music consists of musical phrases. Similar to written and spoken language, a phrase ends with a cadence (a punctuation mark) and is combined with other phrases to form larger formal structures (sentences and paragraphs). Cadences at phrase endings can be open (deceptive, half) and closed (perfect authentic, imperfect authentic, plagal).

In the Common Practice Period, several phrases are often combined into a period. Periods are parallel (similar material opens each phrase) or contrasting (new material in each phrase).

Periods with two phrases

Phrase 1 (antecedent or “question”) ending on a HC
Phrase 2 (consequent or “answer”) ending on a PAC or IAC

or

Phrase 1 (antecedent) ending on an IAC
Phrase 2 (consequent) ending on a PAC

Period with three phrases

Phrase 1 (antecedent) ending on a HC
Phrase 2 (antecedent) ending on a HC
Phrase 3 (consequent) ending on a PAC or IAC

Double period, with four phrases

Two-phrase antecedent:
Phrase 1 ending on a HC
Phrase 2 ending on a HC or IAC

Two-phrase consequent:
Phrase 3 ending on a HC
Phrase 4 ending on a PAC or IAC

Examples of periods

Much music of the Common Practice Period employs motives that unify a phrase and drive the melody towards its cadence. Note the use of motives in the periods below.

1. Parallel Period with Two Phrases

2. Contrasting Period with Two Phrases

Forms

In a manner similar to architecture, musical form refers to the shape and design of large sections of a musical composition.

1. Variation form

A   A¹   A²   A³ …

Examples: Baroque variation form; passacaglia (basso ostinato or repeating bass line); Baroque variation form chaconne (repeating chord progression); also used by Classical composers in theme and variations form.

2. Binary form

A   B
A   A’
||:  A  :||:  B  :||

Example: Baroque dances

||:  A  :||  B     (bar form)
||:  A  :||: B  A’ :||     (rounded binary form)

Examples: each theme and variation in theme and variations form; minuet, scherzo, trio

3. Ternary form

A  B  A’

Examples: minuet and trio, scherzo and trio

4. Alternating forms

A B A C A
A B A C A B A
A B A C A D A

Examples: fugue, invention, ritornello form, rondo form, sonata-rondo form

5. Song forms

Strophic/bridge: A  A’  B  A

Example: First phrase ending on a half cadence, second phrase ending on an authentic cadence, contrasting third phrase, fourth phrase ending on a perfect authentic cadence or deceptive cadence followed by a short coda

Bridgeless: A  B  C  A   or   A  B  A  C
Through composed: A  B  C  D