I'm not sure what to tell you - F8 in Word is still assigned to the
ExtendSelection command & works as expected here in 12.2.4 running on
10.6.3, so whatever is causing it must be at the OS level or external of
Word. Assuming that Office & OS X are fully updated, check the System
Preferences for your keyboard settings as well as any 'helper' utilities you
may have that impose keyboard shortcuts.
Until you get it resolved perhaps using a different method of selecting text
would serve the purpose. For example, if you click in one spot [i.e., start
of a passage] then hold Shift while you click elsewhere [i.e., at the end of
the passage] it effectively selects everything in between. In fact, I find
that to be even more effective because you don't have the hassle of turning
the Extend mode off. See Word Help on the subject of 'Word Keyboard
Shortcuts' - 'Selecting text & graphics' for more.
HTH |:>)
Bob Jones
[MVP] Office:Mac
