Is it possible to use just the definite article with the word "accent" at all times when talking about someone's English? I mean can we say "He speaks with the American accent"? Or do we have to use "a", rather?
By "accent" I mean the brand of English one has been speaking.
Thank you in advance.
I'd say no. I can rattle off at least a dozen regional accents in the US, so there is no single accent.
However, even if there were only one accent, I'd still use "a" to mean "an accent that is American."
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.
There are many different American accents (accents which are used by American people), and many different English accents etc.
If you mean, for example, that someone says "sidewalk" instead of "pavement" then you simply say that they speak American English, not British English. Their accent is irrelevant.
No, use "a" or "an." Even if the accent is well defined and singular, you still do not say "the."
Would that be a sort of mistake to say "He speaks American English", meaning the person was born and bred in the US and does pronounce the r's, for instance?