In Word 97 (I can't speak for more recent versions), and I think in some
other Windows applications as well, if you click with your mouse on any
text while holding down the Ctrl key, the current sentence will be
selected. If you then release the Ctrl key while keeping the Mouse
button depressed, and move the Mouse over the text, the selection will
be extended sentence by sentence as the mouse pointer goes over each
next sentence. This works both left and right.
If you like the ability to extend the selection by sentences (which for
me is indispensable), you may want to access Word's built-in commands
for these functions, SentRightExtend, SentLeftExtend, and assign
keystrokes to them. If you're interested in that, write back to the
group and I'll show you how.
Larry