Tennis equipment

I'm no coach so help me out here anybody, but I tell my girlfriend that a lot of the swing should just be your upper torso rotating. Not that that's the only part, but when I'm shanking the ball a lot I try to get better torque from my shoulders and less from my arm movement.

On the backhand side, if you're like most people who use a two-hander, and are right handed, you should keep in mind that it's your left hand that really controls and drives the swing. Its analogous to a basketball shot how the weak hand just steadies the racquet while the dominant hand actually supplies most of the power.

The main struggle she has keeping up in the longer rallies is her footwork. She doesn't always turn sideways so shes hitting some shots completely open. Also watching pro tennis she thinks the swing has to be continuous and done all at the last second in a blur. I tell her its more important to get your racquet back which also gets your body sideways and ready to move to the ball. I'm starting to hear short choppy steps in her approach which is a good sign, but also I feel like shes getting a better feel for what angles to take to get off a clean shot.

It seems like one day it'll be fun to teach my kids, if I decide to have some/oops.