A combustor for a gas turbine includes a combustor liner that has an outer liner and an inner liner. At least one of the outer liner and the inner liner includes (a) an upstream liner section fixedly connected in the combustor, (b) a downstream liner section fixedly connected in the combustor, and (c) a dilution liner section including a movable portion including at least a part of the dilution liner section and having at least one dilution opening therethrough. The movable portion is arranged to translate in an upstream direction and in a downstream direction. At least one actuator is connected to the movable portion of the dilution liner section and controls translational movement of the movable portion in the upstream direction and the downstream direction to adjust a volume of a primary combustion zone within the combustor.