If I may be permitted a little facetism, once you've pressed <Tab> I don't
think it's possible to press and so on. In fact, I don't think you can do it
by pressing <Tab> only, either.
If C5 is already selected and you want to know how to move the contents of
C5 to C8 by using only the keyboard and not the mouse, try this sequence:
<Shift-Del><Down><Down><Down><Enter>.
If C5 is already selected and you want to know how to move the selection to
C8 without copying or moving any data, just use <Down><Down><Down>.
Or maybe you wanted to do something else?
