On a JV33 (similar machine but without the cutter) it is
 
Function>
down arrow 5 times
Enter>
up and down changes the language
Enter> saves the selection
 
Probably very similar if not the same on your machine.
 
The actual Function menu is called Display. If you can tell what language it is currently in use Google translate to translate "Display" into the language it is set to now then you would know for sure you are on the right Function menu.