cosmology - If you shoot a light beam behind the event horizon of a black hole, what happens to the light?

I have a couple of questions about light here, and sorry of they are silly..

So since anything that goes beyond the event horizon can't go out, so what if a light beam was pointed somewhere behind the event horizon to the outside, would light have a slower speed then get sucked back? and what if the light particles were somehow exactly on the event horizon, would the light stand still? And why can't light stand still? why does it always move at that really high speed?