Hyphens, En Dashes, Em Dashes

Q. Does half need a hyphen when modifying a verb? For example, “He half listened to her story” or “She half walked, half ran.”

A. No hyphen—half may be treated like other adverbs. He barely listened; he half listened. She quickly walked; she half walked.

[This answer relies on the 17th edition of CMOS (2017) unless otherwise noted.]