"Fairer than tongue can speak or thought may frame" begins and ends with an alliterative "f" sound connected to "Form" in the previous line, but also reemphasizing and doubling form and shape in the word "frame." It also deforms the form of the person in question due to the inability to speak or describe it; it is form that is incapable of being form via language but "informed" to the "shadowy dome" of the poem's shape and alliteration.