"My students have been saying it correctly all the time, and I've been telling them that they were wrong," said Maria de Conceição. She had her head in her hands and, while not looking exactly disheartened, she did look somewhat perplexed. She was one of twenty Portuguese teachers of English who were showing pluck and determination by sitting through a twenty-five hour training course with me, and we had been looking at the alarming variety of ways of saying many high-frequency words in English.

Perhaps the most disquieting thing that they had heard  from me was that "RP" (Received Pronunciation) English, which is usually taught as "standard" British English, is spoken by no more than 5% of the British population. The word in question was the fairly humble bath, and the trainees had been listening with ever-slackening jaws as I explained that in England alone — never mind Scotland, Ireland or Wales — it might be heard with an a as in cat (/a/) or else like a in palm (/a:/) or an even longer vowel sound resulting in bahth (/ɑ/). Indeed, this short or long vowel differentiation is one of the key indicators of the difference between speech in the north and the south of England, with a further distinction, a burr, for the southwest.

However, there was more. The trainees then learned that the weak th sound (/θ/) at the end of bath is not always pronounced with the tongue delicately touching the front teeth but might be heard as the f in off. Hence, the word bath might be heard as bath, bahth, bahf or baff, amongst other variations. Discovering the cavalier way in which th is sounded, both the more percussive /ð/ (that, the) and softer /θ/ (with, this), and that it is common to hear them being substituted with a d, t or v, was greeted with some astonishment. Here is a sound which  causes endless grief in the language classroom and no doubt much wailing and gnashing of teeth has accompanied attempts to get to grips with phrases like "through thick and thin" and "seeing things through together," and now the teachers are finding out that perhaps the majority of native speakers don't speak like that anyway.

We were involved in a course on how English is spoken in different parts of the British Isles, and how it got that way. This involved a virtual journey in space and time around some of the 1000-plus islands that make up the British Isles in space and time (we briefly visited Anglo-Saxon Mercia and Viking Northumbria, for example, as well as the most northern and southern points of the archipelago) and, importantly, considered the way that Celtic and Gaelic still impact the way that many of the locals speak in northern and western areas.

This, in particular, led to another surprise in pronunciation which revolves around rhoticity, or the way that rs are articulated. The Portuguese tend to be very exuberant with their r sounds, and if a double rr appears in a word then, be warned, phlegm may fly. Many teachers had been spending much time trying to reduce the natural rhoticity of their students when speaking English and then I came along and pointed out that robust rs abound in the speech of many millions of native speakers, especially in those parts where Gaelic is spoken. So, when their students pronounce 'Is this the right road, then?' as 'Is dis de rright road, den?' with rolling rs, and ds instead of /θ/ and /ð/, rather than being corrected maybe they should have been congratulated for sounding like they were natives of Lancashire.

All very confusing, perhaps, but it did get across my main message, which was to be very careful when teaching what is claimed to be "proper" English. There was a time, perhaps not even 50 years ago, when "proper" British English was considered to be RP — or "the Queen's" or "BBC" English. It was to do with class as much as anything, and the elites — and those who were camp followers of the elites — spoke with refined, if strangled, vowels and emaciated consonants and regarded those who didn't, the 95% who spoke with "regional" accents, with varying degrees of contempt.

It has only been in the last few decades that the BBC — that erstwhile keeper of standards — allowed news readers and announcers with perceptible regional accents to appear. The perception that RP English is "correct" and the rest, well, isn't quite right, y'know, is rapidly waning. Teaching English as a foreign language hasn't quite caught up with the change with this current, sometimes grudging acceptance that there are, indeed, a multitude of "correct" Englishes.

Until now there has been a general perception amongst EFL teachers that we teach either American English or British English, and while they might nod their heads in acknowledgement to the existence of Australian or South African English amongst others, they don't come into the choice. The same question can be asked — whether it is American or British which is chosen — which version should be taught? As there is still a perception that there is such a thing as "standard" American and "standard" British, this is what tends to be taught regardless of how most native speakers actually speak.

During the training course with the Portuguese teachers I conjectured that if we acknowledged the need to teach what we might call educated English rather than standard English — that which was spoken well regardless of accent — then we might be fairer both on the language and on our students. I wasn't advocating that we necessarily teach the kind of English used by hill farmers in North Wales or a construction worker in New Orleans — though I do see a place for making sure out students know about the existence and differences of such diverse accents — but to restrict the oral and aural experiences of the language classroom to only well-rounded and refined accents is hardly doing our students a  service. In the real world it doesn't sound like this at all. It also makes sense to teach a variety of English which most closely resembles the accent that the students speak, so that they don't waste effort and, more importantly, confidence, in trying to acquire the "correct" phoneme sound when in fact another, easier version is not only available but already largely acceptable.

This was all quite shocking news to the teachers on my course. It probably would have given Professor Henry Higgins in Pygmalion/My Fair Lady a heart attack. For students, and for those who believe that learning languages is about increasing and widening communicative ability, then this should be good news. And the brown cows?  I'm not sure they will mind which accent you use when you address them.