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- The police have been on the lookout for that notorious robber for a long time.


Is the phrase "be on the lookout for" natural in formal English only? In a casual conversation / writing, would it be more appropriate to say "The police have been looking for... ."?


Thank you!

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LaboriousIs the phrase "be on the lookout for" natural in formal English only?

No, if anything it's the opposite: "be on the lookout for" is more informal than formal.

Comments  
LaboriousIs the phrase "be on the lookout for" natural in formal English only? In a casual conversation / writing, would it be more appropriate to say "The police have been looking for... ."?

There is another difference. "On the lookout" means that they remain aware that he is wanted as they go about their daily business. "Looking for" means that they are actively trying to find him.