Propinqua benigna coniugem et liberos in atrium ducit.

Because propinqua and benigna are both in the nominative singular feminine, which is the form Latin normally uses for the subject.

Also, the verb ducit is 3rd person singular, so it goes naturally with one singular subject. The other main nouns in the sentence, coniugem and liberos, are in the accusative, which marks them as direct objects.

Here, propinqua is being used as a noun, meaning something like female relative.

The word benigna is an adjective modifying it, so propinqua benigna means the kind relative or a kind relative.

More generally, propinquus / propinqua can also be an adjective meaning near or related, but in this sentence it works as a noun.

Because Latin adjectives must agree with the nouns they describe in gender, number, and case.

So if propinqua is:

• feminine
• singular
• nominative

then benigna must also be:

• feminine
• singular
• nominative

That is why they match.

Because the verb ducit means leads, and the person or people being led are put in the accusative case in Latin.

So:

• coniugem = spouse in the accusative singular
• liberos = children in the accusative plural

Both are direct objects of ducit, joined by et.

Because they come from different declensions.

• coniugem comes from coniunx, coniugis, a 3rd-declension noun.
• liberos comes from liberi, a 2nd-declension plural noun meaning children.

They are both accusative, but different noun families form the accusative differently.

Because Latin uses:

• in + accusative for motion into
• in + ablative for location in

So:

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

Since the sentence involves movement, ducit ... in atrium, the accusative is required.

Ducit is:

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

It comes from ducere, meaning to lead.

So ducit means he/she/it leads or sometimes is leading, depending on context.

Because Latin word order is much more flexible than English word order.

Latin often puts the verb near the end, especially in straightforward narrative sentences. English depends heavily on word order to show who is doing what, but Latin usually shows that through case endings instead.

So this sentence can place ducit at the end without causing confusion.

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

So a noun like propinqua can mean:

• a relative
• the relative

and the exact sense comes from context.

The same is true for coniugem, liberos, and atrium.

No. In this sentence, benigna is an adjective, not an adverb.

It agrees with propinqua, so it describes what sort of relative she is: kind.

If you wanted to say kindly in Latin, you would normally need an adverb, not the adjective benigna.

By itself, coniugem just means spouse. The noun coniunx can refer to either a husband or a wife.

The accusative singular form coniugem does not tell you the spouse's sex by itself. You need:

• context,
• another word in the sentence,
• or the translation already provided.

So Latin here leaves that detail open unless something else specifies it.