preposition usage

jane   Fri Jul 04, 2008 12:10 pm GMT
1.It depends on her
or
It depends upon her.

2.It depends upon the situation
or
It depends on the situation

I would like to know the most preferable and acceptable
usages in these sentences.

Thanks
Skippy   Fri Jul 04, 2008 2:36 pm GMT
Typically you'd say "on," and "upon" sounds a little weird, but it could work, I think.