The first principal part of any verb is the first person, present tense.

Clamo - I shout I am shouting I do shout

The Second principle part is called the INFINITIVE. It means “to (verb)”.

clamare - to shout

The third principal part is the first person singular, present tense. clamavi - I shouted I have shouted I did shout

The third principal part provides the perfect stem.

The last three slides will give you examples of the other conjugations. The other conjugations are not as consistent as first conjugation. The principal parts of verbs should be memorized.

video - I see, I am seeing, I do see

vidēre - to see

vidi - I have seen, I saw, I did see

visus - seen

Duco - I lead, I am Leading, I do lead

Ducere - to lead

Duxi - I have lead, I led, I did lead

Ductus

audiō - I hear, I am hearing, I do hear

audīre - to hear

audīvī - I heard, I did hear, I have heard

auditus - heard