Definition
To be careful about one's behavior and language, especially to be polite and avoid causing offense in a particular situation.
言行舉止得體
You must mind your p's and q's when meeting with the boss.
與老闆會面時，你必須注意言行舉止。
At a formal dinner, everyone must mind their p's and q's.
在正式晚宴上，每個人都必須注意自己的言行舉止。
She always tells the children to mind their p's and q's when visiting relatives.
她總是告訴孩子們在拜訪親戚時要注意言行舉止。