Just lately I find this happening a lot. I'm typing in English and it
'spontaneously' switches to Japanese. I've found the way to fix it is simply
to restart Word, but there must be some short cut keys to this feature that
I am inadvertently pressing.
Any clues
Do you use Japanese and have you installed Japanese as an available
language? If so, then it's possible that you are inadvertently pressing a
key combination that is switching you to Japanese. You can tame this by
changing your language options (right-click the language indicator in the
Windows Taskbar, and choose Settings).

Signature
Herb Tyson MS MVP
Author of the Word 2007 Bible
Blog: http://word2007bible.herbtyson.com
Web: http://www.herbtyson.com
> Just lately I find this happening a lot. I'm typing in English and it
> 'spontaneously' switches to Japanese. I've found the way to fix it is
[quoted text clipped - 3 lines]
> I am inadvertently pressing.
> Any clues