Avus eclipsim praedicit.

Avus is nominative singular. In Latin, the nominative case is typically used for the subject of the sentence—the person or thing doing the action.

Here, praedicit means he/she predicts, so we look for a nominative singular noun to match it. Avus fits, so avus is the subject.

Because eclipsim is the accusative singular form, used for the direct object of the verb.

The dictionary form is eclipsis (meaning eclipse), but in this sentence the eclipse is the thing being predicted, so it must be in the accusative:

• eclipsis = nominative singular
• eclipsim = accusative singular

This noun is a Greek-type noun that keeps a Greek-style accusative in -im.

Eclipsim is accusative singular. It is the direct object of praedicit.

That means it answers the question what does the grandfather predict?

• subject: avus
• verb: praedicit
• direct object: eclipsim

Praedicit is:

• 3rd person singular
• present tense
• active voice
• indicative mood

It comes from praedicere, meaning to predict or to foretell.

So praedicit means he predicts or she predicts. Because the subject is avus, we understand it as he predicts.

Latin has no articles—there is no separate word for the or a/an.

So avus can mean:

• grandfather
• the grandfather
• a grandfather

And eclipsim can mean:

• an eclipse
• the eclipse

The exact English wording depends on context.

Yes, the word order can change more freely in Latin because the endings show the grammatical roles.

For example, these can mean the same basic thing:

• Avus eclipsim praedicit
• Eclipsim avus praedicit
• Praedicit avus eclipsim

However, different orders can give different emphasis. The version you have is a very straightforward order: subject + object + verb.

Because avum would be accusative singular, not nominative.

Compare:

• avus = nominative singular, subject
• avum = accusative singular, direct object

Since the grandfather is doing the predicting, Latin uses avus, not avum.

Yes. Praedicit comes from praedicere:

• prae- = before
• dicere = to say

So the basic idea is something like to say beforehand, which developed into to predict or to foretell.

Its principal parts are:

• praedico
• praedicere
• praedixi
• praedictum

Eclipsis is usually treated as feminine.

So if you later saw an adjective agreeing with it, that adjective would normally be feminine as well.

In this sentence, though, the gender does not visibly affect anything, because eclipsim appears by itself as the direct object.

In a common restored Classical pronunciation, you could say it roughly like this:

• Avus = AH-woos
• eclipsim = eh-KLEEP-sim
• praedicit = pry-EH-di-kit

A few helpful notes:

• v is pronounced like English w in Classical Latin
• c is always hard, like k
• ae sounds like ai in aisle in Classical pronunciation

So the whole sentence is roughly:

AH-woos eh-KLEEP-sim pry-EH-di-kit

Because the subject, avus, is singular.

Latin verbs agree with their subjects in person and number. Since there is one grandfather, the verb is 3rd person singular:

• avus praedicit = the grandfather predicts

If the subject were plural, the verb would also be plural, for example:

• avi praedicunt = the grandfathers predict