Chris O’Dowd let’s his Australian co-star Rose Byrne in on the cúpla focal.

The Roscommon-native and top actress Rose Byrne star in the new comedy  “Juliet, Naked.”

To promote the upcoming release, the comic duo appeared in Vanity Fair’s “Slang School” video series to quiz each other on Irish and Aussie lingo.

Dad-of-two O’Dowd played a blinder with the vernacular from Down Under, nailing the translations of terms like “no wozza”.

However “X Men” star Byrne didn’t quite seem to have the ‘gift of the gab’ when it came to deciphering popular Irish speak.

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In fairness to Byrne, we wonder how most people would fare when presented with statements like "suckin' Diesel".

O'Dowd and Byrne appear in the upcoming romantic comedy, based on Nick Hornby's book of the same name.

The duo previously starred together in the 2011 hit "Bridesmaids".

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