The synonym could be courteous, or cordial, or simply nice.
One possibility is... courteous
Act polite means to be kind and if you don't know what kind means it means to be nice.
Considerate.
congenial
complaisantcondescendingconsiderate
Some synonyms for the adjective nice are:admirableagreeableamiableattractivecharmingcongenialconsideratecordialcourteousfine,friendlyGentlegood,kind,likablelovely.pleasant,polite,well manneredwinsome
The same as today.
It means to set an example to others about being polite. because it originally means kind and nice but the root polis-city comes into polite because being kind and nice should set something for the whole world (city).
The adverb for the word polite would be politely. This means been nice to someone.
Polite, agreeable, genial, favorable.
To be polite means to be kind and courteous to others. Regardless of the situation or circumstances, kindness, good speech, and politeness is always displayed to others.
Some antonyms for the word impertinence are kind, mannered, nice, polite and fine.