In Word when I'm editing a document I select some text and hit the Apple-B (or CMD-B) and it changes the whole document instead of just the selected text...?!

But if I hit the undo combination (CMD-Z) then Word changes it all back to regular (not bold) typeface but leaves the selected text I originally wanted in Bold, now in Bold.

Anyone got any suggestions on how to get this working properly?!

Please help!