ag pronunciation - ow vs ay?
So, Duolingo's TTS voice says, for example, dag as day, slag as slay and svag as svay. But in a YT video I was watching (Danish person making Swedish people try to parrot back some Danish, Swedish people failing miserably) the Danish lady pronounces slag as "slouw" like rhyming with Dutch "vrouw". So, what's the difference?
Usually it is pronounced with an a-sound like in the English "bat" and with a glottal stop, which is what makes it sound a bit like 'ay' as you say.
In some dialects (some parts of Jutland) it is normally pronounced so it rhymes with the English "Cow", and perhaps the Dutch vrouw?
this second pronounciation is common throughout Denmark in some contexts. Standard expressions such as "slag på tasken" (lit. punch on the bag, meaning rough estimate); "slag i slag" (roughly meaning 'step by step'); "frit slag (på alle hylder)" (meaning free choise of everything - "pick and choose").
So both pronounciations are fine. But if you use the second one consistantly, people might think you come from Jutland