Gerund: A gerund is a verb form ending in -ing that functions as a noun. (e.g., Running is good exercise.)
Participle: A participle is a verb form that functions as an adjective. (e.g., The broken vase needs to be fixed.)
Infinitive Phrase: An infinitive phrase consists of an infinitive and any accompanying words or modifiers. (e.g., To win the game was their ultimate goal.)