Quick rules for using avere vs essere as auxiliaries

Italian Tenses Unlocked: Your Easy Guide: Quick rules for using avere vs essere as auxiliaries

Here are quick rules for using avere vs essere as auxiliaries in Italian compound tenses:

Use avere (to have) as the auxiliary verb when the main verb is transitive, meaning it takes a direct object (answers “what?” or “whom?”).
Use essere (to be) as the auxiliary verb when the main verb is intransitive and does not have a direct object, especially verbs of movement or change of state.
Verbs expressing motion or change (like andare [to go], venire [to come], diventare [to become]) generally take essere.
Some verbs can take both auxiliaries depending on meaning and object presence. If the verb has a direct object, use avere; if not, use essere — for example, “ha passato la mattina” (spent the morning - transitive) vs. “è passata all’ufficio” (passed by the office - intransitive).
The past participle agrees in gender and number with the subject only when essere is the auxiliary.
Reflexive verbs and impersonal verbs use essere.
Some movement verbs like camminare (to walk), nuotare (to swim), sciare (to ski), and others are exceptions and take avere even though they indicate movement.
Impersonal and weather verbs usually use essere, but some can appear with avere as well.

In summary, use:

Avere for transitive verbs and some intransitive ones emphasizing the action/activity.
Essere for intransitive verbs indicating movement, change of state, reflexive actions, and impersonal constructions.¹^{, 2}^{, 5}^{, 6}

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