Puer ad matrem fugit, quia tonitrum audit.

Puer is in the nominative singular, which is the case Latin normally uses for the subject of the sentence.

So in Puer ad matrem fugit, puer is the boy, the one doing the action of fleeing/running.

Its basic dictionary form is puer, puerī = boy.

The preposition ad means to or toward and takes the accusative case.

So:

• ad = to/toward
• matrem = accusative form of māter (mother)

Together, ad matrem means to his/the mother or toward his/the mother.

Latin often uses a preposition where English also uses one, and ad is the normal choice here for motion toward a person.

Because after ad, Latin uses the accusative.

The noun is:

• nominative: māter = mother
• accusative: mātrem = mother as the object of a preposition like ad, or as a direct object

So ad matrem literally means toward mother.

Here fugit is 3rd person singular present active indicative of fugiō, fugere.

That means:

• 3rd person singular = he/she/it
• present = is fleeing / flees / runs
• active = the subject does the action
• indicative = ordinary statement

So puer ... fugit = the boy flees/runs.

Yes, in spelling without vowel marks, fugit can be ambiguous.

There are two different forms:

• fugit = he flees / is fleeing (present)
• fūgit = he fled (perfect)

In normal Latin texts, macrons are often not written, so both appear as fugit. You tell which meaning is intended from context.

In a beginner sentence like this, it is usually meant as the present: he runs/flees.

Quia means because and introduces a clause giving the reason.

So:

• main idea: Puer ad matrem fugit = the boy runs to his mother
• reason clause: quia tonitrum audit = because he hears thunder

This is a very common way to express cause in Latin.

Latin word order is more flexible than English word order because the endings show the grammar.

Placing the verb at the end is very common in Latin, especially in simple prose. So quia tonitrum audit is a normal Latin way to say because he hears thunder.

English depends much more on word order, but Latin can move words around for emphasis or style.

Tonitrum is the direct object of audit, so it is in the accusative singular.

The interesting thing is that tonitrum is a neuter noun of the second declension, and for many neuter nouns:

• nominative singular = tonitrum
• accusative singular = tonitrum

So the form looks the same in both cases.

Tonitrum means thunder, a thunderclap, or the sound of thunder.

So in this sentence it is the thing the boy hears:

• tonitrum audit = he hears thunder

A learner may notice that English often uses no article here, and Latin also has no article.

Latin often leaves out possessive words like his, her, or their when the meaning is obvious from context.

So ad matrem can naturally mean:

• to the mother
• to his mother

In this sentence, English usually understands that it is his mother, even though Latin does not say suam.

If Latin wanted to be extra explicit, it could say ad matrem suam.

No, it would not be more correct—just more explicit.

Both are good Latin, but they feel slightly different:

• ad matrem fugit = he runs to his mother/the mother, with possession understood from context
• ad matrem suam fugit = he runs to his own mother, making the relationship clearer or more emphatic

Latin often prefers the shorter version unless there is a reason to stress the possession.

Because the verb ending already tells you the subject is he/she/it.

In audit, the ending -t shows 3rd person singular:

• he hears
• she hears
• it hears

And fugit also has -t, again showing he/she/it.

Since puer is already present, Latin does not need a separate word for he.

Often, yes.

Because the endings show each word’s role, Latin can rearrange the sentence more freely than English. For example, these would still make sense:

• Puer fugit ad matrem, quia tonitrum audit.
• Quia tonitrum audit, puer ad matrem fugit.
• Ad matrem puer fugit, quia tonitrum audit.

The basic meaning stays the same, though the emphasis may shift a little.

Not really in the way it is in English-style teaching texts.

Modern editors often use punctuation to help readers, so a comma before quia is perfectly normal in printed Latin. But ancient Latin manuscripts did not use punctuation the way modern texts do.

So the comma is mainly there to make the structure easier to see:

• main clause
• quia clause giving the reason

Latin’s simple present can cover both ideas that English separates:

• he runs
• he is running

So fugit can be translated in more than one natural English way depending on context.

Likewise:

• audit can mean he hears or he is hearing, though he hears is the more natural English choice here.

They are:

• puer, puerī = boy
• ad = to, toward
• māter, mātris = mother
• fugiō, fugere = flee, run away
• quia = because
• tonitrum, tonitrī = thunder, thunderclap
• audiō, audīre = hear

Knowing dictionary forms helps you identify why the actual sentence uses forms like matrem, fugit, and audit.