What are the principal parts of a Latin verb?
When you look up a verb in a Latin dictionary, it will almost
always give three or four words. These are the principal parts. For
example, the principal parts of 'to love/like' are amo, amare,
The first part is the singular, 1st person, present, active,
indicative form of the verb. In the case of 'to like', this is
amo, which means 'I like'.
The second part is the present, active infintive. amare =
The third part is the 1st person, singular, perfect, active,
indicative form. amavi = 'I liked/I have liked'.
The final part, which not all verbs have, is the masculine
singular perfect passive participle. amatus = 'having been
liked'. Usually, this can be translated into more natural-sounding
English when in a sentence. Intransitive verbs (ones without a
direct object, such as 'to walk' or 'to run', have no fourth part.
(Some dictionaries give a different form, the supine, as the fourth
principal part. This is a distinction without much of a difference,
since the supine is identical to the participle except that it ends
in -um instead of -us.)
In deponent verbs (verbs which are always formed in the passive
voice, but which have an active meaning, such as conor, conari,
conatus sum, 'to try', only ever have three parts, which are
the same as the first three parts of a normal verb. by removing
sum from the third part, we can find the perfect active
participle (only deponent verbs have perfect active participles
instead of perfect passive participles); in this case,
conatus, 'having tried'.