It must consist of exactly fourteen lines of iambic pentameter.
The meter is iambic pentameter; but the first foot of the second line is a trochee, and emphasizes thoughts with fine effect.
Unrhymed poetry, usually in iambic pentameter measure, is known as blank verse.
The sonnet is a lyric poem consisting of fourteen iambic pentameter lines.
The average quatrain is in iambic ...