There are three regular sets of verbal conjugations, and various verbs are irregularly conjugated. Within each of these sets of conjugations, there are four simple (one-word) verbal conjugations by person/number in the indicative mood (present tense; past tense with imperfective aspect, past tense with perfective aspect, and future tense), two simple conjugations in the subjunctive mood (present tense and past tense), one simple conjugation in the conditional mood, and one simple conjugation in the imperative mood. Corresponding to each of the simple conjugations, there is a compound conjugation involving a simple conjugation of "to be" or "to have" followed by a past participle. "To have" is used to form compound conjugation when the verb is transitive ("Ha detto", "ha fatto": he/she has said, he/she has made/done), while "to be" is used in the case of verbs of motion and some other intransitive verbs ("È andato", "è stato": he/she has gone, he/she has been). "To be" may be used with transitive verbs, but in such a case it makes the verb passive ("È detto", "è fatto": it is said, it is made/done). This rule is not absolute, and some exceptions do exist.