You raise a valid point, communication is a key aspect to how we relate to others. Whilst I am able to communicate reasonably well in 2 'european' languages, this is far from the norm - especially in the UK. We have developed, possibly because of our empire past, an arrogance that assumes everyone will understand english - you just have to speak it slowly and loudly enough.
(sorry, my personal rant there)
But lets take the central assumption that English is to be defined as a core common language of European communication. You rightly point out that even within England, let alone the rest of the UK, there are distinct regional dialects and accents. Traditionally this was resolved by the adoption of "BBC English" which was a fairly neutral, southern accent, however there has been an increase in the media for more tolerance of regional accents.
Learning to read phonetically is actually something I still have to engage brain with, I do not do it 'day to day'.
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As you suggest, probably the best way to approach this is to start them young, and teach it from nursery/primary school age (4/5 years old) so that they understand how to read phonetically, and to appreciate how "standard" english should sound. This does carry the warning that standard english should not be taken to be superior to regional accents. The same is true in France, where despite the best efforts of the Academie Francaise to maintain the highest standards of French, regional and international variations creep in.
an interesting side-effect of teaching children to read and speak phonetically is that it may assist with learning foreign languages, as they can see the correct way to pronounce words - no more me speaking French like an englishman <sigh>, or german like a chinese person apparently
btw, this is an old one, but it illustrates the problems with spelling and pronunciation - based on pronunciation of words, FISH could be spelled GHOTI
GH as in the F of ENOUGH
O as in the I of WOMEN
TI as in the SH of FICTION
indeed in your example of 'correct' pronunctiation I read "houp" as the same way as 'hoop' but it could be pronounced 'hup or 'hop'' - the difference in pronouciation between COULD, TOUGH and COUGH[/size]