be on the lookout for

US /bi ɑn ðə ˈlʊkˌaʊt fɔr/
UK /bi ɑn ðə ˈlʊkˌaʊt fɔr/
"be on the lookout for" picture
1.

estar atento a, estar à procura de

to be actively watching or searching for something or someone

:
We need to be on the lookout for any suspicious activity.
Precisamos estar atentos a qualquer atividade suspeita.
The police are on the lookout for the escaped prisoner.
A polícia está à procura do prisioneiro foragido.