Puella nubilis sponsalia facit.

Because nubilis is a third-declension adjective, not a first/second-declension one like bona or alta.

It still agrees with puella in:

• gender: feminine
• number: singular
• case: nominative

But agreement in Latin does not mean the endings have to look the same. It just means the forms match grammatically.

So:

• puella = nominative singular feminine noun
• nubilis = nominative singular feminine adjective

They go together even though one ends in -a and the other in -is.

Puella is nominative singular.

Its job is to be the subject of the verb facit. In other words, the girl is the one performing the action.

The phrase puella nubilis together forms the subject:

• puella = girl
• nubilis = marriageable / of marriageable age

Nubilis is an adjective modifying puella.

In this sentence it is:

• feminine
• nominative
• singular

It describes what sort of girl is meant: a marriageable girl, or a girl of marriageable age.

It is also related in meaning to the verb nubere, to marry (from the woman’s perspective in classical Latin usage).

Facit is:

• third person singular
• present tense
• active voice
• indicative mood

It comes from facio, facere, to do / make.

So grammatically it means he/she/it does or makes.
Here, because the subject is puella, it means she does/makes.

Here sponsalia is accusative plural, the direct object of facit.

A learner might wonder about this because with many neuter nouns, the nominative plural and accusative plural look the same. So how do we tell?

We tell from the sentence structure:

• puella nubilis is clearly the subject
• facit is a singular verb
• sponsalia is what the girl is doing or making

So sponsalia must be the object.

Because sponsalia is one of those Latin nouns that is normally used in the plural.

So even though Latin has a plural form, English may translate it naturally as:

• engagement
• betrothal

This is very common when moving between Latin and English: the number in Latin does not always match the most natural number in English.

It is partly literal, but this is best understood as an idiomatic expression.

The phrase sponsalia facere means something like:

• to arrange a betrothal
• to contract an engagement
• to become engaged

So while facit by itself means makes/does, the full expression has a more specific social meaning.

Yes, the order could be different.

Latin word order is much more flexible than English word order because the endings show the grammatical relationships. So:

• puella nubilis
• nubilis puella

can both mean the same basic thing.

Putting the adjective after the noun is perfectly normal Latin. Different word orders can create slightly different emphasis, but the grammar stays clear because of the endings.

Because Latin has no articles.

So puella can mean:

• a girl
• the girl

Which one is best depends on the context.

English has to choose an article, but Latin usually leaves that idea unstated unless the context makes it clear.

You should think of puella nubilis as a single noun phrase: the marriageable girl.

The adjective nubilis is not standing on its own. It is attached to puella and describes it.

So the sentence divides neatly like this:

• Puella nubilis = subject
• sponsalia facit = predicate

That is often a helpful way to read Latin: first find the subject phrase, then the verb, then the object.