"Why do you say b/ʊ/s? and why not b/ʌ/s?"
The question is referring to the fact I, like most people from Yorkshire in England, pronounce that word as if I have just been lightly jabbed in the guts.
" Because I'm from North England" I always reply
This answer always seems to disappoint the teacher. It seems they were hoping for a walking example of perfect English and instead got an extra from 'Billy Elliot'.
Of course, the reality is that there isn't such a thing as a 'perfect accent'.
Something brilliantly described by Hugh Dellar on his FB vlogs and website here:
http://www.lexicallab.com/2015/05/politics-pronunciation-and-the-pursuit-of-perfection/
What is a British accent?
So the truth is there is no 'British accent' despite what American sit-coms might think. School text books use recieved pronunciation (RP) as the standard because, hey, they have to put something! But, in the real world of English communication, 97% of British speakers have an alternate accent. Are they wrong? Are their accents 'worse' than RP?
They aren't, and the quicker we make students aware of differences in accent the better.
That's why good modern text books use videos and audios that include people from different parts of the world, both native and non-native speakers.
So what should we teach?
I don't believe we should teach students that they have to copy 'British accents' or RP. The focus of English lessons should be helping the students to communicate with people from around the world, not on training them to be like British people (who don't speak like that anyway). If students are able to pronouce words intelligibly and can communicate in English then I believe we shouldn't make them feel that it's wrong to have an accent when they speak.
As a teacher I just pronounce a word how I would pronounce it naturally, the students do the same and if we all understand each other that's fine.
So should we correct?
If one of my students pronounces /V/ as /W/ as they can't distinguish between the sounds, then yes I correct it. This confusion could be because the student is unable to hear the difference, so I would help them to identify the two sounds. However, if the student has a Ukrainian accent due to sentence or word stress I believe this totally fine. As I tell students, 'It's ok to have a Ukrainian accent, you are Ukrainian'.
Most of what the students learn isn't English as a Foreign Language(EFL) anymore, it's English as a Lingua Franca (ELF). So British norms are becoming less relevant. Do we need to teach our students RP when they are unlikely to ever encounter anybody speaking like this?
Having an accent is part of who we are. After all, Billy Elliot wouldn't have been the same in RP!