How should we write the phrase "one of a kind"? [closed]
I see no justification for the hyphens, except in the unlikely circumstance of the phrase being used adjectivally.
Depends.
Is the expression used as a single adjective before a noun? If so, use hyphens (see example 1). For example: "He is a one-of-a-kind man."
Is the expression used as a predicate adjective after the verb to describe a noun before the verb? If so, don't use hyphens (see example 2). For example: "That man is one of a kind."