Mary Oliver wrote “Wild Geese” in free verse, which means that the poem doesn’t conform to any previously established metrical forms. Instead, it has its own unique form. This form is not bound by any repeating metrical pattern or rhythmic regularity, but instead flows freely in a naturalistic style that, to some ears at least, may seem closer to prose than to poetry. Although Oliver doesn’t force metrical regularity on her language, she does carefully control the lengths of each line in such a way that gives the poem a distinct, shifting pace. For instance, consider the difference between the very abbreviated opening sentence and the longer, more grammatically complex sentence that follows it in lines 1–3:

     You do not have to be good.
     You do not have to walk on your knees
     for a hundred miles through the desert, repenting.

In addition to the difference between the lengths of the two sentences, notice how each line gets longer than the last one. This progressive lengthening creates a sense of language stretching itself out, taking up space and elongating time. The lengths of the sentences contract in the subsequent lines, only to expand once again as the poem reaches its conclusion. This dynamic of contraction and expansion nicely reflects the themes of self-punishment and self-liberation at the poem’s heart.