often I write in English and in Italian in the same document for this reason I wonder if is possible to use at the same time the Italian and the English dictionary.


I’m afraid not. You can switch which dictionary you’re using in the Auto-Correction tab of Tools>Options, as you probably know, but it’s only possible to have one dictionary selected at a time.

what a pity.

The problem is that with options (enables):
.- check spelling as you type;
.- correct spelling errors as you type;
.- Dictionary: Italian
every time I write a word in English this is automatically changed to an Italian word that does not make sense…

Understandable. Your best option here is to turn off auto-correction–maybe even the “check spelling as you type” option as well, and just run the spell check after you’ve finished typing, so you’re not distracted with a lot of red underlines from the “foreign” language. You can click “Ignore” as well, which will prevent the underlining and the auto-correction, but since you’re going to have a lot of words coming up like that it will probably be more tedious than it’s worth.