1. Irregular Verbs
sum, possum, volo, nolo

2. Regular Verbs reviewed
Regular verbs belong to one of 4 conjugations. The infinitive ending determines which conjugation: -are = 1st conjugation -ēre = 2nd conjugation -ere = 3rd conjugation -ire = 4th conjugation Regular verbs follow a set pattern of rules about how to conjugate them. The rules can be summarized in the following chart.
1st conj.
2nd conj.
3rd conj.
4th conj.
Infinitive Ending
-are
-ēre
-ere
-ire
Present Linking Vowel a e i
Imperfect Linking Vowel ie

3. sum, esse, fui, futurus – to be possum, posse, potui – to be able
Irregular Verbs
Irregular verbs have infinitives that don’t match the endings of regular verbs. Their present and imperfect tenses need to be memorized.
sum, esse, fui, futurus – to be
possum, posse, potui – to be able
volo, velle, volui – to want
nolo, nolle, nolui – to not want

4. Sum, esse, fui – to be
Present Tense Singular Plural 1st person: sum sumus 2nd person: es estis 3rd person: est sunt Imperfect Tense Singular Plural 1st person eram eramus 2nd person eras eratis 3rd person erat erant

5. Possum, posse, potui – be able
Present Tense Singular Plural 1st person: possum possumus 2nd person: potes potestis 3rd person: potest possunt Imperfect Tense Singular Plural 1st person poteram poteramus 2nd person poteras poteratis 3rd person poterat poterant

6. Volo, velle, volui – to want
Present Tense Singular Plural 1st person: volo volumus 2nd person: vis vultis 3rd person: vult volunt Imperfect Tense Singular Plural 1st person volebam volebamus 2nd person volebas volebatis 3rd person volebat volebant

7. Nolo, nolle, nolui – to not want
Present Tense Singular Plural 1st person: nolo nolumus 2nd person: non vis non vultis 3rd person: non vult nolunt Imperfect Tense Singular Plural 1st person nolebam nolebamus 2nd person nolebas nolebatis 3rd person nolebat nolebant