A course of modern english lexicology

2. METRE

In poetry, the metre is the basic rhythmic structure of a verse. Many traditional verse forms prescribe a specific verse meter, or a certain set of meters alternating in a particular order.
Prosody is a more general linguistic term, that includes poetical metre but also the rhythmic aspects of prose, whether formal or informal.
The scansion of a poem is the analysis of its metrical structure.
Metre gives systematization of English verse and rhythm determined by the relationship between the stressed and unstressed syllables.
The unit of measure of rhythm is called the ‘foot’. It is the smallest recurring segment of the line, consisting of one stressed syllable and one or two unstressed ones.
The structure of the foot determines the metre, i.e. the type of poetic rhythm of the line. There are five basic feet in English poetry:
A. Trochee
The foot consists of two syllables, the first one is stressed.
 (duty, evening, honey, pretty)
B. Iambus
The foot consists of two syllables, the second one is stressed.
 (mistake, enjoy, again, behind)
C. Dactyl
The foot consists of three syllables, the first one is stressed, the subsequent two are unstressed.
 (wonderful, beautiful, certainly, dignity)
D. Amphibrach
The foot consists of three syllables, the first one is unstressed, the second one is stressed, the third one is unstressed.
 (returning, continue, pretending, umbrella)
E. Anapest
The foot consists of three syllables, the first two are unstressed, the third one is stressed.
 (understand, disagree, interfere)

Trochee Men of England, wherefore plough For the lords who lay ye low? Wherefore weave with toil and care The rich robes your tyrants wear? (Shelley)