# Latin I/3rd Declension Lesson 3

Salvēte omnēs!
This is our third lesson covering the 3rd declension of Latin nouns. For a guide to previous lessons and a classified vocabulary list, be sure to check out the links on the right.

## New Grammar

This time, we will introduce the 3rd declension i-stems. These have the reputation of being tricky; in fact, they are listed as #28 in Latin Student Problems on Tumblr. (We just have to share this for the benefit of all the Latin geeks on Wikiversity!) So, anyway, back to grammar.
We have learned some regular m/f and regular neuter nouns of the 3rd declension in 3 of the cases (and I strongly encourage lots of review of the previous lessons in this declension, since there is so much complexity here). I-stem nouns differ from the regular nouns in having an extra -i- before the ending of the genitive plural. In addition, neuter i-stems have the -i- show up in the nominative and accusative plural, and it is substituted for the -e ending of the ablative singular. But there are not very many neuter i-stems in common use, so the most frequent variant you will see is the one in the genitive plural. Clear as mud? Here are the differences highlighted on this chart:
| case name | sing. | pl. | typical use |
| nominative (m./f.) | --- | -ēs | subject or predicate noun |
| nominative (n.) | --- | -(i)a | “ |
| genitive | -is | -(i)um | possession, the “of” case |
| dative | -ī | -ibus | indirect object, the “to/for” case |
| accusative (m.) | -em | -ēs | direct object (also some objects of preps.) |
| accusative (n.) | --- | -(i)a | “ |
| ablative | -e | -ibus | objects of prepositions, etc. “by/with/from” case |
I-stem nouns have some rules/guidelines that distinguish them from regular 3rd declension nouns, but it might be most helpful just to memorize them as part of your vocabulary study. The vocabulary page will have a model declension for each type of 3rd declension noun. There is also a pretty good survey of 3rd declension nouns (PDF) at The Latin Library that may help to clarify this for you. All the nouns introduced this lesson will be 3rd declension i-stems, and we will particularly focus on the genitive endings in this lesson (but we’ll look at some of the regular nouns too so you can see the difference.) Also note that there are 3rd declension adjectives (there is a teaser for them at the very end of the sentences this lesson) but we won’t be formally introducing them until later.

## New Vocabulary

| Latin | English |
| cīvis, cīvis, cīvium (c.) | citizen |
| collis, collis, collium (m.) | hill |
| hostis, hostis, hostium (c.) | enemy |
| mare, maris, marium (n.) | sea |
| mōns, montis, montium (m.) | mountain |
| mors, mortis, mortium (f.) | death |
| nox, noctis, noctium (f.) | night |
| pars, partis, partium (f.) | part |
| urbs, urbis, urbium (f.) | city |

## New Sentences

| Latin | English | Notes |
| Cīvis Rōmānus/Rōmāna sum. | I am a Roman citizen. | |
| Cīvēs Rōmae sumus. | We are citizens of Rome. | |
| Cīvēs urbis sunt. | They are citizens of the city. | |
| Cīvēs multārum urbium estis. | You are citizens of many cities. | |
| Est magnum perīculum in montibus. | There is great danger in the mountains. | |
| Perīculum montium magnum est. | The danger of the mountains is great. | |
| Mors mātrum et patrum est mala. | The death of mothers and fathers is bad. | |
| Pars hostium in montibus est. | Part of the enemies is in the mountains. | |
| Vīrtus cīvium magna est. | The courage of the citizens is great. | |
| Parvus frāter magnum timōrem mortis habet. | The little brother has great fear of death. | |
| Amīcus mātris meae vīllam in colle habet. | My mother’s friend has a house on a hill. | |
| Collis est altus. | The hill is high. | |
| Rōma est urbs collium. | Rome is a city of hills. | |
| Et urbs rēgum est. | It is also a city of kings. | |
| Mare est altum. | The sea is deep. | |
| Nox est longa. | the night is long. | |
| Terra hostium multōs montēs habet. | The land of the enemy has many mountains. | |
| A marī usque ad mare. | From sea to sea. | |
| Labor omnia vincit. | Work conquers all. | |
| Omnia amor vincit. | Love conquers all. | Virgil wrote both of these originally. n.b. 3rd declension adjectives are i-stems. |

## Practice

Practice and learn the words and phrases in this lesson :
| Step one | First learn the words using this lesson: 3rd Declension vocabulary |
| Step two | Next try learning and writing the sentencing using this: 3rd Decension Sentences |
| AI version | You can try learning and writing the sentences using our AI Prompt |
| Note that the Memrise stage covers the content for all lessons in each stage. If you are skipping previous stages you may need to manually "ignore" the words in previous levels (use the 'select all' function) ||
That’s a fairly good introduction to i-stems, although there’s a lot of complexity we haven’t touched yet. We’ll have one more lesson on the 3rd declension, focusing on the dative case, and then we will try to give you some lessons that are more topical (food, family, etc.) and less grammatical. Bonam fortūnam!