Iambic Tetrameter

Poetry is measured speech. Its words are organized in rhythmic patterns called meter. The most common pattern or meter for English poetry is the iambic foot, which is composed of two beats, the first unaccented and the second accented. Most often in English poetry, the iambic foot appears in lines of five feet called iambic pentameter, but lines can be shorter or longer. Blake's “A Poison Tree” is in iambic tetrameter, four iambic feet, but a variation on that pattern is common throughout the poem. In most of the lines, the second beat of the last foot is truncated, or cut off.

The first line of “A Poison Tree” offers an example of truncated iambic tetrameter. “i WAS / anGRY / with MY / friend” is a line with three and a half feet. The second line is a full tetrameter line. There are four complete iambic feet: “i TOLD...