There are some key differences in how people from Sunderland and Newcastle speak. To outsiders, these aren't noticeable - but kind of those who know, know.

In mackem (my mother tongue) - we pronounce cheesy chips like - 'cheyzey chips'. Whereas in Geordie it's more 'chizzy chips'.

Mackems pronounce y's more prominently in words where there isn't one, this, also gave birth to jibes like "weyze keys are theyze keys" (whose keys are these keys).

Geordies similarly don't pronounce the u vowel well. So house (hoose), mouse (mooss) are probably the equivalents. In fact I regularly used "is there a mooss loose aboot ya hoose" in retort to any cheesey chip or weeze keys jibes.

Because people in the north east are actually very similar, we tend to sieze on these subtle differences to show how different we are. Which is ironic really so in practice it works more like an inside joke to northerners who knows this.

100% mackem but love the city of Newcastle, and the people. Except on derby day 🤣