Great Regulars: [W.S.] Merwin was among those who, in the 60s,

began to loosen the screws of formal verse. He grew into his mature style in the later 60s and 70s, when he moved toward the curiously impersonal voice and "open" style that have become his trademark. As he began to write his own kind of free verse, he layered image upon bright image, allowing the lines to hang in space, largely without punctuation, without rhymes, as in the final stanza of "Thanks," where he writes with a kind of graceful urgency:

from Jay Parini: The Guardian: Why WS Merwin deserves his second Pulitzer prize

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