Mater flores in mensa disponit.

Because mater is in the nominative singular, the case normally used for the subject.

Here that makes sense with the verb too:

• mater = mother
• disponit = she arranges / is arranging

So mater is the one doing the action.

A learner may also notice that English often relies on word order, but Latin relies much more on case endings. Even if the word order changed, mater would still be the subject as long as it stayed nominative.

Because flores is the accusative plural here, so it is the direct object: the thing being arranged.

Its dictionary form is flos, floris (flower).
The form flores can be either nominative plural or accusative plural, but in this sentence it must be accusative because:

• mater is already the subject
• disponit is singular, so it cannot go with a plural subject like flores

So flores means flowers as the object: Mother arranges the flowers.

Here mensa is ablative singular.

The preposition in takes:

• the ablative for location: in/on the table
• the accusative for motion toward: into/onto the table

So:

• in mensa = on the table / in the table area
• in mensam = onto the table

Since the sentence describes where the flowers are being arranged, not movement onto the table, Latin uses the ablative.

Without macrons, mensa can look the same in the nominative singular and ablative singular.

You know it is ablative here because of the preposition in:

• in + ablative = location
• in + accusative = motion into/onto

If macrons were written, the ablative would be shown as mensā.

So context and syntax tell you the case, even when the spelling looks the same in a text without macrons.

Latin in has a wider range than English in. With the ablative, it can mean in, on, or sometimes simply at, depending on context.

With a table, English naturally says on the table, but Latin can still use in. So in mensa is best translated idiomatically as on the table here.

In other words, the Latin is normal even if the English uses a different preposition.

Disponit is:

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

It comes from dispono, disponere, meaning arrange, set out, or put in order.

The ending -t is the key sign of he/she/it in the present tense.
So disponit means she arranges, he arranges, or it arranges. Here, because the subject is mater, the natural translation is she arranges.

Classical Latin has no articles like English the or a/an.

So:

• mater can mean mother, a mother, or the mother
• flores can mean flowers, some flowers, or the flowers

The exact English choice depends on context. In a basic sentence like this, English usually supplies the if that sounds most natural.

Because the verb ending already includes that information.

In disponit, the -t tells you the subject is 3rd person singular: he/she/it. Since the sentence already has mater, Latin does not need an extra pronoun.

Latin can add a pronoun such as ea, but that would usually add emphasis, something like she herself or that woman depending on context.

Yes. Latin word order is much more flexible than English word order because the case endings show what each word is doing.

So all of these could express roughly the same basic idea:

• Mater flores in mensa disponit
• In mensa mater flores disponit
• Flores mater in mensa disponit

The difference is mainly emphasis:

• starting with mater can emphasize the doer
• starting with flores can emphasize the flowers
• starting with in mensa can emphasize the location

The version you were given is a perfectly normal Latin sentence.

No. Grammatical declension and natural gender are not the same thing.

Mater is a third-declension noun:

• nominative: mater
• genitive: matris

It is feminine in gender, but it does not belong to the first declension.
That is why its forms do not look like mensa, mensae.

This is a very common thing in Latin: a noun can be feminine without being first declension.