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sometime, sometimes, some time

sometime: adverb meaning at some indefinite time:
            I'll be there sometime.

Sometime is not hyphenated in compound modifiers.

sometimes: adverb meaning occasionally:
            Sometimes articles editors disagree with the editorial Style Manual.

some time: adverbial phrase meaning an interval:
            He left some time ago
            the Style Manual has been under revision for some time.

See also: someday, some day.