Latin question: How do you tell if an adjective is 1st, 2nd, or 3rd declension?

[Sunshine State Sue]

I understand how to figure out the noun declensions and the verb conjugations, but I don't seem to be able to wrap my head around adjective declensions.

 

Thanks!

[Plaid Dad]

There are really only two groups of adjectives, those that borrow their endings from the 1st/2nd noun declensions (there are a few irregular ones in this group), and those that borrow theirs (with some small changes) from the 3rd noun declension.

 

The 1st/2nd declension adjectives are those that end in -us, -a, -um, and you will usually see those endings when you look the word up in a Latin dictionary. If the noun you're modifying is masculine or neuter, these adjectives will use the same endings as 2nd declension masculine or neuter nouns. If the noun is feminine, the adjective will take 1st declension endings. For example (these are all nominative singular forms):

 

magnus fluvius, a big river

magna insula, a big island

magnum oppidum, a big town

 

Third declension adjectives come in a bunch of variations. Any Latin grammar book will give charts with examples.

 

It is entirely possible to have a 1st or 2nd declension noun modified by a 3rd declension adjective (gladius brevis, a short sword) or a 3rd declension noun modified by a 1st/2nd declension adjective (ovis parva, a little sheep).

 

Clear as mud? :)

[Sunshine State Sue]

Actually, that was very helpful. You stated about all I had been able to figure out, and I must have looked at it enough times for it to be sinking in. Somehow, I thought it had to be more complicated...

 

Thanks! :hurray:

[Plaid Dad]

Glad to help! :)