Know your place - Idioms by The Free Dictionary
know your place
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know (one's) place
To be aware of one's role in a particular place or situation. I know my place, so I don't bother the CEO when I see him around the office. I am just an intern, after all!
know your ˈplace behave in a way that shows that you know what your social position is and which people are more important than you: My grandfather believed that life was simpler when he was young, when everybody knew their place.