" My Life Closed Twice Before Its Close" is written in two quatrains, or stanzas of four lines each, arranged in iambs. The iamb is a metric foot of two syllables in which the first syllable is unstressed and the second stressed. It is the basis for the most common line pattern in English verse.

The first and third lines of each quatrain are in iambic tetrameter, which means that there are four jambs in each line ("tetra" meaning four). In the alternate, and rhyming, lines, Dickinson changes to a three-foot meter called iambic trimeter ("tri" meaning three). For a lesser poet, such a fixed metrical pattern might have been a creative limitation. However, Dickinson, whose genius was her ability to choose the perfect word above all others, used the simplicity of this familiar stanza pattern to showcase the power of language without distraction.

One interesting aspect of this...