Cable RF - stereo or mono?

Pardon my newbie question please....

we have a stereo-ready tv, but our VCR is mono only.

Our cable RF goes directly into the VCR antennae in, then back out the
the TV via RF out.

if the original signal from the cable company is stereo, what happens
when we route the RF signal thru our VCR? Does it retain the stereo
audio split via the RF cables, or, does it automatically convert to
mono?

How much programming does a "typical" cable company boradcast in
stereo? I am assuming that not much of the big network stuff, ABC,
NBC, etc, is broadcast in stereo..... am i wrong?