A Korean student is schooling the world in how to speak Mackem.
Seong-Jae Kong, from South Korea, has become an Internet sensation after posting a series of videos on YouTube under the name Korean Billy, in which he accurately mimicks a wide range of British accents and dialects.
And now he has turned his attention to Wearside.
'Billy,' who has already posted videos covering accents including Scouse, Geordie and Yorkshire, has produced a new short film exploring Mackem words and phrases.
And he highlights the difference between how Wearsiders speak compared to their near neighbours: "Some people confuse Mackem with Geordie, but they are totally different.
"And before taking a look at some Mackem words, you should remember that Sunderland is also called 'Sunlun' by local people."
He goes on to explain the meaning of the word 'Marra' and adds: "People often say 'Nee bosh, marra,' and this means 'No problem, mate'."
Billy outlines the difference between Wearside's 'Ha'way' and Tyneside's 'Howay' before looking at how the Mackem uses of an 'ew' sound for '00' turns 'book' and 'school' into 'bewk' and 'skewel'.