Sentence:  Hard surface cleaning in household application is represented by two classes of alkaline products : ( 1 ) the formulations made expressly for <WSD>machine</WSD> dishwashers , and ( 2 ) the general-purpose cleaners used for walls and woodwork . 
Meaning of the word marked with <WSD> tags:  any mechanical or electrical device that transmits or modifies energy to perform or assist in the performance of human tasks