Third declension adjectives are declined in the same way as third declension I-stem nouns. So we already know the endings; we just need to know how to find the stem. You'll recall that with first and second declension adjectives, we memorized all three genders in the nominative singular (bonus, bona, bonum), so we could drop the ending from the feminine (or neuter) to get the stem. Third declension adjectives work similarly, but with more variety.

There are three types of third declension adjectives, depending on how many different endings they have in the nominative singular masculine, feminine, and neuter.

These adjectives always end in -er in the masculine, -is in the feminine, and -e in the neuter. Drop the -is ending from the feminine (or -e from the neuter) to get the stem, ācr-, and decline like a third declension I-stem noun:

These words end in -is in both masculine and feminine, so rather than repeat it twice (like fortis, fortis, forte), we memorize the two different endings and know that the first ending always applies to masculine and feminine both. It is declined the same:

We say these have one ending because the nominative shares the same ending in all three genders—in this case, audax. Since that doesn't help us figure out the stem, we also learn the genitive singular form, just like we do with a noun, so we can drop the -is from it to get the stem. Declining then follows the same familiar rules:

That's all there is to it. The only tricky part is remembering that when you see two forms, you might be looking at a two-ending adjective or a one-ending adjective plus its genitive. To tell the difference, remember that two-ending adjectives always end in -is in the first part (masculine and feminine) and -e in the second part (neuter). One-ending adjectives may have all sorts of irregular endings in the first part, but they will always end in -is in the genitive second part.

And the three-ending ones are easy to spot, since they have three endings and always follow the -er, -is, -e pattern.

Since the two-ending types always have the same stem in both forms, they will sometimes be shown with the second form abbreviated to the ending, the same way regular first and second declension adjectives often are:

• bonus, -a, -um, good
• brevis, -e, short

• ācer, ācris, ācre, sharp, fierce
• audāx, audācis, bold, daring
• brevis, breve, short
• celer, celeris, quick, swift
• difficilis, difficile, hard, difficult
• dulcis, dulce, sweet, pleasant
• facilis, facile, easy
• felix, felicis, fruitful, favorable; lucky; happy (single ending!)
• fortis, forte, brave; strong
• gravis, grave, heavy; serious, severe
• omnis, omne, all, every
• potēns, potentis, powerful (single ending!)
• similis, simile, similar, alike

(And a few first and second declension adjectives:)

• beatus, -a, -um, happy, blessed
• Britannus, -a, -um, British
• Gallus, -a, -um, Gallic
• Trōiānus, -a, -um, Trojan

Gravis means both serious as in a punishment or situation, and heavy in a physical sense. So, just as heavy in English has been common slang for “Whoa, dude, that's serious,” it always had that second meaning in Latin.

Omnis is very commonly used in the plural without a noun to mean everyone (omnēs) or everything (omnia). As a plural, it takes a plural noun, which may not be obvious since everyone and everything are singular in English.

Beatus often shows up in the Mass before the Epistle: Lectio Epistolae beati Petri Apostoli. - A reading (lectio) from the letter of blessed Peter the Apostle.

Felix has the double meaning of both being happy, but also things which make us happy by being fruitful or lucky. The context should show which is meant.

1. dux potēns
2. animal breve
3. femina fortis

1. We were blessed when the king gave our town much money.
2. My brother's horses are swift and fierce.
3. Marcus, your journey to Spain will be long and difficult.
4. Everyone was shouting when the soldiers walked through the gate.
5. We stood near the river and waited for Marcus's swift ship.
6. Julius gave (his) enemy a serious wound with a sword.
7. All the girls liked Lucius because of (his) fast, beautiful horses.
8. The British leader was powerful and fierce throughout the war.
9. If we are lucky, our trip to Spain will be short and easy.
10. When the general was in Rome, he gave gifts to the bold men there.

Find an English word related to each Latin word in the vocabulary.

Three declensions completely finished; only two to go. The fourth and fifth declensions have no adjectives, so they'll be a breeze after the first three.

I keep thinking I'll be able to start mixing in some prayers and Scripture passages soon, but it's hard to find any of those that don't contain a lot of pronouns, and we haven't gotten to those yet. Maybe I'll jump ahead a few chapters next week and hit some pronouns, to open up the possible exercises a bit.

1. dux potens

1. animal breve

1. femina fortis

1. We were blessed when the king gave our town much money. - Beati eramus ubi rex pecuniam multam urbi nostrae dabat.
2. My brother's horses are swift and fierce. - Equi fili mei sunt celeres et acres.
3. Marcus, your journey to Spain will be long and difficult. - Iter tuum ad Hispaniam, Marce, longum et difficile erit.
4. Everyone was shouting when the soldiers walked through the gate. - Omnes clamabant ubi milites per portam ambulaverunt.
5. We stood near the river and waited for Marcus's swift ship. - Stetimus ad flumen et exspectavimus navem celerem Marci.
6. Julius gave (his) enemy a serious wound with a sword. - Julius inimico vulnerem gravem gladio dedit.
7. All the girls liked Lucius because of (his) fast, beautiful horses. - Puellae omnes Lucium ob equos celeres pulchros amaverunt.
8. The British leader was powerful and fierce throughout the war. - Dux Britannus erat potens et acer per bellum.
9. If we are lucky, our trip to Spain will be short and easy. - Si felices sumus, iter nostrum ad Hispaniam erunt breve et facile.
10. When the general was in Rome, he gave gifts to the bold men there. - Ubi imperator in Roma erat, ibi viris audacibus dona dedit.

• ācer, ācris, ācre, sharp, fierce - acrid, acrimony
• audāx, audācis, bold, daring - audacious
• brevis, breve, short - brief, brevity
• celer, celeris, quick, swift - celerity, accelerate
• difficilis, difficile, hard, difficult - difficult
• dulcis, dulce, sweet, pleasant - dulcimer, dulcet
• facilis, facile, easy - facile, facilitate
• felix, felicis, fruitful, favorable; lucky; happy - felicitous, Felix the cat
• fortis, forte, brave; strong - fortify, fortitude
• gravis, grave, heavy; serious, severe - grave, gravity
• omnis, omne, all, every - omnibus, omnivore
• potēns, potentis, powerful - potential, potent
• similis, simile, similar, alike - similiar, simile
• beatus, -a, -um, happy, blessed - beatify