be on your best behaviour
US /bi ɑn yʊər bɛst bɪˈheɪvjər/
UK /bi ɑn yʊər bɛst bɪˈheɪvjər/
1.
comportarse de la mejor manera, portarse bien
to act in the most polite and proper way possible, especially in a situation where you want to make a good impression
:
•
When you meet my parents, I expect you to be on your best behaviour.
Cuando conozcas a mis padres, espero que te comportes de la mejor manera.
•
The children were told to be on their best behaviour during the school trip.
Se les dijo a los niños que se comportaran de la mejor manera durante la excursión escolar.