Puella patrem in atrio exspectat.

Because puella is in the nominative singular, which is the case normally used for the subject of a sentence.

• puella = nominative singular of a first-declension noun
• the subject is the person or thing doing the action
• here, the verb exspectat is he/she/it waits, so puella is the one doing that action

A native English speaker often expects subject position to tell them who the subject is, but in Latin, the ending is usually more important than the word order.

Because patrem is the accusative singular form, and the accusative case is normally used for the direct object.

• dictionary form: pater = father
• accusative singular: patrem

So if someone is waiting for the father, Latin marks father as the direct object with the accusative ending.

This is a very common thing in Latin: nouns change form depending on their role in the sentence.

Atrio is ablative singular.

The preposition in can take:

• the ablative for location: in = in / on
• the accusative for motion into: in = into

Here the idea is location, not movement, so Latin uses the ablative:

• in atrio = in the atrium

So atrio is ablative because the phrase tells you where the action happens.

Yes. That is an important distinction in Latin.

• in + ablative = location, in / on
• in + accusative = motion toward, into / onto

So:

• in atrio = in the atrium
• in atrium = into the atrium

In this sentence, there is no idea of movement into the atrium, only being there, so atrio is correct.

The -t shows that the verb is third person singular in the present tense.

So exspectat means:

• he waits
• she waits
• it waits

Since the subject is puella, the meaning is she waits.

This is one of the most useful verb endings to learn early:

• -o / -m = I
• -s = you
• -t = he/she/it
• -mus = we
• -tis = you plural
• -nt = they

Latin word order is much more flexible than English word order because the endings already show each word’s job.

In this sentence:

• Puella patrem in atrio exspectat

the order is perfectly normal, but other orders could also be possible, such as:

• Puella in atrio patrem exspectat
• Patrem puella in atrio exspectat
• In atrio puella patrem exspectat

These do not usually change the basic meaning. They mainly change emphasis or style.

English depends heavily on word order; Latin depends much more on inflection.

Most naturally, it describes the setting of the action: the waiting happens in the atrium.

In practice, that usually means the girl is in the atrium while waiting. However, Latin prepositional phrases can sometimes leave a little room for interpretation unless context makes it completely clear.

So the most straightforward understanding is:

• the girl is waiting in the atrium

If someone specifically wanted to make another meaning clearer, they could add context or choose a different wording.

Latin does not have articles like English the and a/an.

So a noun like puella can mean:

• girl
• a girl
• the girl

And patrem can mean:

• father
• a father
• the father

The context tells you which sense is best.

This is very normal in Latin, and English speakers have to get used to not seeing articles written out.

Yes. They are related historically, but you should not assume they always mean exactly the same thing.

Latin exspectare often means:

• to wait for
• to look for
• to expect

In this sentence, the sense is clearly wait for.

This is a good example of why English derivatives can help, but they are not always a perfect guide to meaning.

They come from three different noun patterns:

• puella = first declension
• pater = third declension
• atrium = second declension, neuter

That is why their endings look different:

• puella → nominative singular in -a
• patrem → accusative singular of pater
• atrio → ablative singular of atrium

One sentence like this is a good reminder that Latin uses several declensions at the same time, and you have to identify each noun by its own pattern.

It could be, but Latin does not need to follow English habits.

A very common neutral Latin pattern is to place the verb near the end of the sentence. That is what happens here:

• subject: puella
• object: patrem
• prepositional phrase: in atrio
• verb: exspectat

So this word order feels natural in Latin prose. It is not the only possible order, but it is a very ordinary one.

A common Classical pronunciation would be roughly:

• puella = poo-EL-la
• patrem = PAH-trem
• in atrio = in AH-tree-oh
• exspectat = ek-SPEK-taht

A few helpful points:

• ae is not present here, so puella has separate vowels: pu-el-la
• x sounds like ks
• c is always hard in Classical Latin, though there is no c in this sentence
• the final -t is pronounced

If you are using an ecclesiastical pronunciation system, some sounds may differ slightly.