>But there is no difficulty for distinguish /o/ from /u/:-)
Of course it isn't. But that one replaces the other
and vice versa is a common occurrence in many a
language. After all, even your family name, Moeller,
is a proof of this: any German-language speaker will
know that the bearer (or the ancestors) comes from
Northern Germany, while the Muellers are at home in
central and Southern German-speaking territories.
Coz ö<->ü behave like o<->u (and this is valid for
Hungarian too; e.g. in some Transylvanian areas
Hungarians tend to dialectally say [lu:] while in
other areas of Hungary and in the standard language
they say [lo:] - both meaning "horse." As for the
ö<->ü alternance, just have a look at the family
names Szücs & Szöcs (cf. the Romanianized Suciu),
= "furrier.").
>all of these will do not help to derive "cot"
>from "kubitus" trough an "kut" since "u" remains "u".
Ach was! Just imagine sort of a "kuyit", then
"kuut", then with the [u:] pronounced rather as
an [o:] and thusly your "cot" easily pops up. :^)
>the fact that "u" is supposed to become
>"i"
BTW: u is indeed hardly interchangeable with e
and i; but with o easily. If I'd pronounce "bocora-te!",
"tortoreaoa", "am potot colege" you'll understand
everything instantly. The same applies to such
pronunciations as "$ubanu cu cupilu" (as the joke
goes) or "cocorigo" instead of "cucurigu". :)
George