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Latin for Duolingo: 4th Declension Nouns

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Salvete omnes! Welcome back to Latin for Duolingo. If you would like to catch up, you can find past lessons in the directory, a classified vocabulary list, and a Memrise course at these links:

In previous lessons we’ve studied nouns of the 1st, 2nd, and 3rd declensions. Check the directory to review these lessons! They are foundational to all the rest of the course. With a basic knowledge of the first 3 declensions, or classes, of nouns, we have access to the vast majority of Latin nouns. But there are two more declensions, and although they contain a comparatively much smaller number of nouns, some of them are important and frequently used nouns. So now seems a good time to add those declensions and master their inflected forms.

New Grammar

Let’s start with the 4th declension this week. At first glance, the nominative singular base form of a 4th declension noun looks like the 2nd declension masculine nouns, and the gender of most of these nouns is masculine also. However, all three genders are represented in the 4th declension. Masculine and feminine nouns share the same endings, and the much rarer neuter forms have slight variants. I’m giving the macrons (accents over vowels) in the case table, but it’s not practical for me to do that as a regular thing, so please excuse the inconsistency. The main thing you have to be careful with in this declension is how similar it looks to the 2nd declension. Many of the nouns seem to be derived from related verb forms, e.g. “auditus = hearing”. As with all Latin nouns, you can identify the declension by the genitive singular ending, in this instance –ūs, which is why it is always given in the vocabulary entries.

case name | sing. | pl. | typical use
nominative (m./f.) | -us | -ūs | subject or predicate noun
nominative (n.) | -ū | -ua
genitive | -ūs | -uum | possession, the “of” case
dative | -uī (-ū) | -ibus | indirect object, the “to/for” case
accusative (m./f.) | -um | -ūs | direct object (also some objects of preps.)
accusative (n.) | -ū | -ua
ablative | -ū | -ibus | objects of prepositions, etc. “by/with/from” case

The following are 4th declension nouns I’ve introduced in previous lessons:

domus, us (f.) = house, home (has some variant forms, particularly the locative domi “at home”; domum used alone means “to home” and domo used alone means “from home”)
fructus, us = fruit, produce
habitus, us = condition, appearance; suit of clothes
sinus, us = (originally, the fold of a toga used to store valuables), pocket
vestitus, us = clothing

All 4th declension nouns can be assumed to be masculine unless their gender is specifically listed.

New Vocabulary
adventus, us = arrival, approach, coming
exercitus, us = army
gustus, us = taste
idus, uum (f., pl.) = the Ides, the middle of a Roman month
impetus, us = attack
manus, us (f.) = hand, power
odoratus, us = smell, sense of smell
portus, us = harbor, port
reditus, us = return, returning, income, rent
senatus, us = senate
sensus, us = sense
spiritus, us = spirit, breath
tactus, us = touch, sense of touch
visus, us = sight, seeing

New Sentences
Navis est in portu. = The ship is in the harbor.
Naves in portum veniunt. = The ships come into the harbor.
Marcus laborem in manibus habet. = Marcus has the work in his hands/ Marcus is taking care of it.
Quinque sensus sunt visus, auditus, tactus, gustus, et odoratus. = The five senses are sight, hearing, touch, taste, and smell.
Sum tecum in spiritu. = I am with you in spirit.
Est mortuus; non est spiritus in corpore ejus. = He is dead; there is not breath in his body.
Domus mea in urbe est. = My house is in the city.
Oppidum tuum multas domus habet. = Your town has many houses.
Lucia domi non est. = Lucia is not at home.
Lucia domo abest. = Lucia is away from home.
Pater domum venit. = Dad comes home.
Tunica manu facta est. = The tunic was made by hand.
Manus meae sunt rubrae. = My hands are red.
Milites impetum faciunt. = The soldiers make an attack.
Idus Martiae = The Ides of March, March 15
Mors Caesaris Idibus Martiis erat. = The death of Caesar was on the Ides of March.
Gaius in senatu est. = Gaius is in the senate.
Reditum Marci exspecto. = I am waiting for the return of Marcus.
Adventum Paulae exspectamus. = We are waiting for Paula’s arrival.
Habesne reditum domui? = Do you have the rent for the house?
Multi milites in exercitu sunt. = Many soldiers are in the army.
Exercitus in Galliam venit. = The army comes into Gaul.
Senatus populusque Romanus (SPQR) = The Senate and People of Rome. (Official title of the Roman government).
Fructu non foliis arborem aestima. = Judge a tree by its fruit, not its leaves.
Multorum manibus magnum levatur onus. = By the hands of many a great load is lifted/ Many hands make light work.

Enough for this time; next lesson will delve into the 5th declension. Please feel free to comment or ask questions below, and I will do my best to respond. Bonam fortunam!

2 years ago


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they should definitely make a latin course - they're making a greek one :) yay ancient languages

2 years ago

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Well they're making modern Greek, ancient Greek can be quite different (but not entirely)

2 years ago