Finite / non finite
This word applies only to certain verbs. A verb in a sentence can exist on its own as in these examples: ‘It’s good to exercise’ or ‘I enjoy exercising’. In each of these sentences, the form of the verb is termed non-finite.
Alternatively – and every complete grammatical sentence has one at least by definition – the verb can be made finite. This simply means that it is ‘attached’ grammatically to a subject word and shows inflexions that determine its grammatical usage such as number (they visit) , person (she speaks well) and tense (he spoke yesterday).
