Mater vicinas benigne accipit et eis gratulatur, quod filias suas tam diligenter curant.

Because vicinas is the direct object of accipit.

• accipit = she receives / welcomes
• The person or thing being received is put in the accusative
• So vicinae becomes vicinas

In this sentence, Mater is doing the action, and vicinas are the ones receiving that action.

Because gratulor, gratulari takes the dative case, not the accusative.

So:

• eis = to them
• gratulatur eis = she congratulates them

This is very common in Latin: some verbs take different cases from what an English speaker might expect. Even though English says congratulate someone, Latin uses a structure closer to offer congratulations to someone.

Because gratulatur comes from a deponent verb.

A deponent verb:

• has passive forms
• but an active meaning

So:

• gratulatur looks like he/she is congratulated
• but it actually means he/she congratulates

This is something English speakers often have to get used to in Latin. The form is passive-looking, but the meaning is not passive.

Here quod means because.

It introduces the reason for the congratulating:

• eis gratulatur = she congratulates them
• quod filias suas tam diligenter curant = because they care for their daughters so carefully

So quod is acting as a causal conjunction.

Because the subject of curant is not Mater. It is the neighbors.

The sentence works like this:

• Mater ... accipit et eis gratulatur
  = Mother welcomes the neighbors and congratulates them
• quod ... curant
  = because they care for their daughters carefully

The subject of curant is understood from vicinas / eis. In other words, the neighbors are the ones doing the caring, so the verb is plural.

Because suas is the reflexive possessive adjective and refers back to the subject of its own clause.

In the clause:

• filias suas tam diligenter curant

the subject is they = the neighbors. So suas means their own.

That is exactly what Latin wants here: the neighbors are caring for their own daughters.

If Latin used earum instead, it would usually mean the daughters of those other women, not their own.

Filias suas is accusative plural.

Why?

Because it is the direct object of curant:

• curant = they care for
• whom do they care for? filias suas

Both words are feminine accusative plural:

• filias = daughters
• suas = their own

The adjective suas matches filias in gender, number, and case.

Because it describes how the mother welcomes the neighbors, not what kind of person she is.

• benigne = kindly
• benigna would mean kind as an adjective describing a noun

So:

• Mater benigne accipit = Mother welcomes them kindly

This is the normal Latin way to express manner: use an adverb with the verb.

It is an adverb phrase.

• diligenter = carefully
• tam = so

Together:

• tam diligenter = so carefully

Here tam strengthens the adverb diligenter. It tells us the degree of care.

Yes.

Mater is:

• nominative singular
• the subject of both accipit and gratulatur

Even though mater does not end in -a like many first-declension feminine nouns, it is a third-declension noun.

So the sentence begins with the subject: Mother.

Yes. Latin word order is much freer than English word order because the endings show the grammatical roles.

For example, this sentence could be rearranged in several ways and still mean basically the same thing, as long as the case endings stay clear.

The current order is useful because it presents the sentence neatly:

• subject: Mater
• object: vicinas
• verb: accipit
• then the second action: eis gratulatur
• then the reason clause: quod ... curant

So the order is natural, but not the only possible one.

Yes. The subject is not stated explicitly, but it is understood to be the neighbors.

Latin often leaves out subject pronouns when the verb ending already shows the person and number.

• curant = they care for
• Who are they? From context, the neighbors

So Latin does not need to repeat a separate word for they.

It has two main verbs in the main clause, plus a subordinate clause giving the reason.

Main clause

• Mater vicinas benigne accipit
• et eis gratulatur

Subordinate clause

• quod filias suas tam diligenter curant

So the pattern is:

• Mother welcomes the neighbors kindly
• and congratulates them
• because they care for their daughters so carefully

This is a good example of how Latin can combine:

• a direct object with one verb
• a dative with another verb
• and then a quod clause explaining why