colloquialism vs keep one's eyes open

colloquialism is a noun but keep one's eyes open is not a noun.

Word	Noun	Adjective	Verb	Adverb
colloquialism	Yes	No	No	No
keep one's eyes open	No	No	Yes	No

colloquialism (noun)	keep one's eyes open (noun)
a colloquial expression; characteristic of spoken or written communication that seeks to imitate informal speech

colloquialism (verb)	keep one's eyes open (verb)
	pay attention; be watchful