Maybe, when you try to learn English in Spain you don't realize that you really know nothing about pronunciation. .
I mean, once your are in UK, Canada or wherever you want, you find out that your vocabulary is not so huge as you thought before and you discover there are 20 different sounds for 5 vocals.
And YES, a lot of times is really important to know how to pronounce these strange sounds.
And NO.. you can't rely on the context when you use words like:
--beach or bitch
-- shit or sit or sheet, or seat.
-- Paul, pole
-- leave, live
-- chess, cheese
I've just found this link. It's really bad, but...
But it is what it is.. and I guess it's better to stop know because I'm putting myself off... :-/