Humanities › History & Culture How to Conjugate the Irregular Latin Verb Sum "To Be" The Proper Conjugations of Esse Share Flipboard Email Print "I am a Roman citizen." A proud graffito on via dell'Umiltà. CC BY 2.0 by antmoose History & Culture Ancient History and Culture Ancient Languages Figures & Events Greece Egypt Asia Rome Mythology & Religion American History African American History African History Asian History European History Genealogy Inventions Latin American History Medieval & Renaissance History Military History The 20th Century Women's History View More By N.S. Gill Ancient History and Latin Expert M.A., Linguistics, University of Minnesota B.A., Latin, University of Minnesota N.S. Gill is a Latinist, writer, and teacher of ancient history and Latin. She has been featured by NPR and National Geographic for her ancient history expertise. our editorial process N.S. Gill Updated November 28, 2019 The Latin word sum is perhaps among the best known of all the Latin verbs and it is among the hardest to learn. Sum is the present indicative tense of the verb esse, meaning "to be." As with many other living and dead languages, esse is one of the oldest verb forms in Latin, one of the most frequently used of the verbs, and one of the most irregular verbs in Latin and related languages. It is also often contracted in casual use (such as in English I'm, that's, they're, he's), so that the verb is almost invisible to the listener. Etymology The progenitor form of "to be" is in the Proto-Indo-European (PIE) language, the parent language of Latin, Greek, Sanskrit, Iranian, Germanic, and indeed most of the languages spoken in all of Europe, India, and Iran. Each of the PIE languages has a form of "to be," perhaps because it is so eminently useful: sometimes "to be" can have an existential significance ("To be or not to be," "I think therefore I am"), but also retains its use in everyday language. In etymological circles, to be is the b-root word, and like all of the b-roots probably is derived from an ancient PIE root, today reconstructed as *h1és-mi (I am). It is also possible that "to be" in Latin derives from the root word *bhuH- meaning "to grow." Other closely related words to esse are asmi in Sanskrit and ešmi in Hittite. Conjugating Sum Mood Tense Person Singular Plural indicative Present First sum sumus Second es estis Third est sunt Imperfect First eram eramus Second eras eratis Third erat erant Future First ero erimus Second eris eritis Third erit erunt Perfect First fui fuimus Second fuisti fuistis Third fuit fuerunt Pluperfect First fueram fueramus Second fueras fueratis Third fuera fuerant Future Perfect First fuero fuerimu Second fueris fueritis Third fuerit fuerint Subjunctive Present First sim simus Second sit sitis Third sit sint Imperfect First essem essemus Second esses essetis Third esset essent Perfect First fuerim fuerimus Second fueris fueritis Third fuerit fuerint Pluperfect First fuissem fuissemus Second fuisses fuissetis Third fuisset fuissent Irregular Verbs and Compounds There are several other Latin irregular verbs and compound verbs formed from sum. Eo - to go Fio - to become nolo, nolle, nolui - 'to be unwilling' and malo, malle, malui 'to prefer' are similar. Volo - to wish Fero - to carry Sum - to becompounds: adsum, desum, insum, intersum, praesum, obsum, prosum, subsum, supersum Do - to give Edo - to eat Sources Moreland, Floyd L., and Fleischer, Rita M. "Latin: An Intensive Course." Berkeley: University of California Press, 1977.Traupman, John C. "The Bantam New College Latin & English Dictionary." Third Edition. New York: Bantam Dell, 2007. Moods of Latin Verbs: Indicative, Imperative and Subjunctive Understanding the Types of Verbs in English Grammar Irregular Latin Verb - Eo Irregular Latin Verb - Nolo Latin Verbs and Infinitives Conjugate the Irregular French Verb Boire (to Drink) What Are the Principal Parts of Latin Verbs? Beginners' Guide to Latin Verb Tenses The 1st Conjugation Verbs in Latin What Are Irregular Verbs in English? Conjugate the Irregular French Verb Connaître, to Know Italian Participle Spanish Verb Salir Conjugation, Translation, and Examples All About 'Dormir,' an Irregular French Verb Like 'Partir,' 'Sortir' Latin Verbs: Their Person and Number Conjugating the German Verb Wissen, Meaning "to Know"