Regular verbs are those whose past tense and past participles are formed by adding a -d or an -ed to the end of the verb. "To roll" is a good example of a regular verb: roll, rolled, rolled. All verbs, whether regular or irregular, have five forms [often called principal parts]. These forms are the infinitive, simple present, simple past, past participle, and present participle. The difference between a regular and an irregular verb is the formation of the simple past and past participle.
