be on (one's) good behavior



be on (one's) good behavior

To be very polite or exercising exceptionally good manners. Primarily heard in US. Now, you kids must be on your good behavior for your Auntie this weekend! Good morning, class. I hope everyone was on their good behavior for the substitute teacher yesterday.
See also: behavior, good, on

Common Names:

NameGenderPronouncedUsage
&Thorn;ÓRir-Icelandic, Ancient Scandinavian
KathieKATH-eeEnglish
Saxa-Ancient Germanic
Nicodemonee-ko-DE-mo (Italian), nee-ko-DHE-mo (Spanish)Italian, Spanish, Portuguese
Dulcie['dʌlsi]
Egemen-Turkish