PROBLEM

In the version of Linux Mint Mate and LMDE Mate, there isn't the Language Support that is instead placed in Menu -> Control Centre in the Cinnamon version.

I would like, therefore, to change the language from Italian to English for reasons binding my study of British English ... writing here is also a good exercise adding to passion for Computer Science....

SOLUTION

Open the "Terminal" from "Menu" and type

sudo   pluma   /etc/default/locale

( type password); (pluma is the specific editor of Mate version, in Cinnamon is gedit)

and appear

LANG  =  it_IT.UTF-8

Now you can erase or silence it, but I prefer don't erase it and choose to silence it by means for comment

#LANG = it_IT.UTF-8

LANG = en_GB.UTF-8

Reboot and at the next Login Window  you find the flag of UK under your username. If you choose to come back to the flag of Italy it's sufficiently to click of the UK flag.....

NOTE:  for American English the script is   LANG = en_US.UTF-8. Thank you in advance for the every comment and every construction criticism and for any suggest that improves my knowledge of English culture........