Ch 4 · Lesson 17Latin · Chapter 4 · Lesson 17 · Grammar primer
The fourth declension: manus, exercitus
Genitive -us, dative -ui, ablative -u: , , . A small family of very common nouns, and looks like until you check the genitive. The fifth and come next.
The short version
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Why?Hide
The fourth declension has a genitive singular in -us and shows itself in the dative -ui and the ablative -u: , , . It holds mostly masculine nouns built off verbs, such as , , , and , plus feminine and . Its nominative is indistinguishable from a second-declension one, so once again the genitive is the form that settles it. And on its own is four different forms.
The fourth and fifth declensions are small families with very common members: (thing), (day), (house) and (hand) are all in the top 140 words. The fourth has a genitive in -us, the fifth in -ei. Here they are side by side.
| Form | Fourth: manus | Fifth: res |
|---|---|---|
| Nom sg | | |
| Acc sg | | |
| Gen sg | | |
| sg | | |
| Abl sg | | |
| Nom/acc pl | | |
| Gen pl | | |
| /abl pl | | |
The fourth runs on -u-, the fifth on -e-. Both reuse one ending in several slots, so the sentence around the noun matters more than usual.
The fourth declension: manus
Spotted by a genitive in -us, and confirmed by a dative in -ui and an ablative in a bare -u. fills four slots with one form, and an adjective or the verb tells you which:
| Slot | Latin | English |
|---|---|---|
| Nom sg | . | A large band is coming. |
| Nom pl | . | Large bands are coming. |
| Acc pl | . | I see large bands. |
| Gen sg | | part of the band |
The noun did not change; everything around it did.
What is in it
Most fourth-declension nouns are made from verbs: the noun for the act of doing it.
| Verb | Noun | English |
|---|---|---|
| , | use, experience |
exerceo | , | a trained force, an army |
| , | feeling, sense |
| , | movement |
| , | a fall, chance |
Not every member fits: comes from , old man, since the senate was the council of elders.
Gender is masculine by default: , a great army. The exceptions worth the ink are and , both feminine ( ), and a few neuters in -u such as , horn, with the plural .
Going further: The fifth declension: res and dies and the rest of the guide, when you want them. This lesson does not need them.
Practice
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One question at a time, mixed across the exercises in this lesson. Miss one and it comes back round before the end.
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