The term 'They Take Turns' can be broken down into three words: Rotors, Doorknobs, and DIALS. Rotors are rotating parts of a machine, such as the blades of a helicopter or the vanes of a turbine. Doorknobs are handles used to open and close doors. DIALS are circular instruments used to adjust settings, such as the volume on a radio or the temperature on an oven. All three of these items take turns in order to function properly.