be on the lookout for

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

留意, 搜尋

to be actively watching or searching for something or someone

:
We need to be on the lookout for any suspicious activity.
我們需要留意任何可疑活動。
The police are on the lookout for the escaped prisoner.
警方正在搜捕越獄的囚犯。