An infinitive irregular verb happens when the word "to" is placed in front of the verb in its simplest form. Examples of infinitive irregular verbs include to think, to blow and to write. The infinitive forms of irregular verbs are used as sentence subjects, sentence objects and description words.
Irregular verbs in past tense are action words that show something that has already happened. When a regular verb is conjugated into past tense the ending "ed" is added. Irregular verbs do not follow this pattern. When an irregular verb is conjugated into past tense, the word often changes. Examples of past tense irregular verbs include thought, blew and wrote.
According to Purdue University's Writing Lab, present participle irregular verbs are action words that end in "ing." Irregular verbs in present participle form are used as adjectives, or words that describe a person place or thing. Examples of present participle irregular verbs include thinking, blowing and writing.
Like the present participle form, past participle irregular verbs are used as adjectives, as indicated by Purdue University's Writing Lab. Unlike the present participle, past participle irregular verbs often alter from the original action word. Examples of past participle irregular verbs include thought, blown and written.