To have a good head on ones shoulders

Context 1
Jim: I like the new quarterback on our high school football team this year.
Steve: Yeah, me too.  He is a very good player and he seems like he has a good head on his shoulders.


Context 2
Sara: I heard we hired a new secretary for the office.
Amy: Yes, her name is Suzie.  She is a very hard worker and she has a good head on her shoulders.

Meaning: This American idiom is used to describe someone who is acts maturely and has good, sound judgement.

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