Infinitive
An Infinitive is “to” plus a verb, used as a noun, adjective or adverb.
Present Participle
A Present Participle is a verb plus “ing,” used as an adjective or a verb.
Past Participle
A Past Participle is a verb plus “-ed,” used as an adjective or a verb.
Verb: Principal Parts
Infinitive Present Past Present Participle Past Participle
To be:
to be am, are, is was, were being been
To do:
to do do, does did doing done