7

I am working on word endings in Latin, and I came across the word Ago. And I was looking at the different conjugations for this word and it did not make sense to me.

Observe:

Endings are:

         o/m   |   mus

         s     |   tis

         t     |   nt

But, when ago is conjugated, this happens:

        Ago | Agimus 

       Agis | Agitis          

       Agit | Agunt

Why is it conjugated with an i?

3
  • 7
    It belongs to the third conjugation. Most verbs in the 3rd conjugation form the different persons of the present tense the same: -o, -is, -it, -imus, -itis, -unt. Thus lego-legis, scribo-scribis, etc. Or do you mean how did the 3rd conjugation evolve to get to that?
    – Rafael
    Oct 5, 2016 at 19:10
  • 2
    @Rafael, I think the question is why the third declension uses -i- (and -u-!) or how things evolved that way. A simple answer is "to avoid consonants in the endings colliding with consonants in the stem", but I doubt that would be satisfying.
    – Joonas Ilmavirta
    Oct 5, 2016 at 21:02
  • 1
    To keep it simple, 3rd conjugation is ALMOST* always: {an O, 4 I's, and a U}. Hope this helps
    – Luke H
    Feb 12 at 2:52

2 Answers 2

15

If you're asking how the third conjugation historically came to use the vowels i/u, it has to do with regular sound changes that affected the original Proto-Indo-European (PIE) endings.

The present indicative active paradigm for this verb in PIE, with its descendant paradigm in Latin, would look something like this:

1sg. *h₂eǵ-ō > agō
2sg. *h₂eǵ-e-si > agis
3sg. *h₂eǵ-e-ti > agit
1pl. *h₂eǵ-o-mos > agimus
2pl. *h₂eǵ-e-tes > agitis
3pl. *h₂eǵ-o-nti > agunt

In PIE, as you can see, the personal endings were preceded by a so-called "thematic vowel", either e or o (except in the 1sg.). This vowel then underwent the following changes in Latin:

  1. In non-initial open syllables, all vowels (basically; there are some exceptions) in Latin became i. This is the source of the i in agimus, agitis.
  2. e became i before a word-final consonant. This is what happened in agis, agit, where first the final -i of the PIE form was lost (as also in the 3pl.), leaving the s/t word-final.
  3. o became u before a nasal (again not absolutely always, but in many cases). This gives the u of agunt.
2
  • While I doubt that this what the OP was wondering about, this is too great not to upvote :)
    – brianpck
    Oct 6, 2016 at 13:26
  • 1
    @TKR, Although it doesn't help me conjugate the verb, I can now understand why in the world it would suddenly conjugate to something like 'agit'. (I know I will learn to conjugate more effectively later on, so that is not really a big deal!) Thanks so much for the input - I truly appreciate it. Oct 7, 2016 at 13:11
9

To ask “why” is inevitably a question about etymology and Indo-European (IE) comparative linguistics. The Latin 3rd conjugation continues IE thematic presents. There is a root, then the “thematic vowel” *e or *o, and then the personal ending. In Latin *e regularly becomes /i/ before /s/ and /t/. Thus IE *bher-e-ti becomes bharati in Sanskrit, but *ferit > fert in Latin, while *bher-o-nti becomes Sanskrit bharanti, and Latin ferunt. Does that make it any clearer? I am not sure that it does. Reconstructed languages are just as inscrutable as real ones.

0

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.