Auxiliary verbs, also known as helping verbs, are used in Slovenia to form different tenses, moods, and voices of other verbs. They are crucial to convey various temporal relationships between different actions or states. The most common auxiliary verbs in Slovenian include ‘biti’ (to be), ‘imeti’ (to have), and ‘morati’ (must). These verbs often accompany the main verb and provide additional information about the action.