Car Starts light Shaking

Recentaly my 99 Cavalier has light shaking when I am around 70 to 80 mph and it has some shaking just when I am around 65 Does anyone know what could be wrong?

Check you tire pressure.

Tire pressure should be 32psi cold, not hot, completely cold.

If that doesn't help, rotate your tires or get them rebalanced.

Also check your lug nut torque. Uneven torquing of the lug nuts can cause symptoms similar to a warped rotor and/or out of balance wheels, which is what your symptpms indicate.