Understanding the intentions of a play is so key because you can block a guy into the running back if you don't know how the play is supposed to work or where the back is going to come out.
I've had to work by myself at combines before and forced myself to work out alone all the way back to high school. You have to be self-motivated.
Obviously it's more fun having my teammates there and having all that camaraderie, but individual workouts are not a loss.
I try to work on all aspects of my game, whether it be run, pass. I think you can never stop growing, and I definitely take that mindset. You've just got to keep on grinding.