This workbook aims to answer one of the most common questions posed by students of Italian as a foreign language: how do you know which auxiliary verb to choose when using compound tenses? Essere (to be) or avere (to have)?This comprehensive workbook is easy-to-use, providing clear tables and useful hints and suggestions to dispel any doubts about whether to use 'essere' or 'avere'.The book is divided into two sections: the first provides helpful thematic tables and explanations; the second presents a range of exercises and activities for ample practice.Beginners - Lower intermediate level (CEFR A1-B1).