Fifth Declension: res, dies

Level 4

Fifth declension nouns end in -es, and the genitive and dative singular end in -ei.

How It Works

Case	res (thing)	plural	dies (day)	plural
nominative	res	res	dies	dies
genitive	rei	rerum	diei	dierum
dative	rei	rebus	diei	diebus
accusative	rem	res	diem	dies
ablative	re	rebus	die	diebus

This is a small declension. The words to know are res (thing, matter), dies (day), fides (faith), spes (hope) and facies (face).

Res is everywhere: res publica is the state. Dies takes a masculine adjective in most sentences: dies longus.

Fides and spes are usually singular.

A dictionary shows the declension in the genitive. A noun listed as res, rei belongs to the fifth declension.

Quot dies habet annus?
How many days does a year have?
Dies is the accusative plural and the object of habet.
Dies longus est, nox brevis.
The day is long, the night is short.
Dies is masculine here, so the adjective is longus.
Res publica Romana magna est.
The Roman state is great.
Res is the nominative singular, and publica agrees with it.
Spes mea in Deo est.
My hope is in God.
From Psalm 61:8. Spes is nominative singular and feminine.
Fides tua te salvam fecit.
Your faith has saved you.
From Matthew 9:22. Fides is the subject, and salvam agrees with te.

Giving res a second declension ending.
Marcus de reis bonis loquitur.
Marcus de rebus bonis loquitur.
Res belongs to the fifth declension, so the ablative plural is rebus. The ending -is belongs to the first and second declensions.

Tap a pattern to see what it builds on and what it leads to.

Fifth Declension: res, diesLevel 4

The fifth family is the last set of endings.

resdies

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