Mater et pater adsunt, sed ceteri adhuc absunt.

Because mater et pater together form a compound subject: mother and father. In Latin, just as in English, two singular nouns joined by et (and) normally take a plural verb.

So:

• mater adest = mother is present
• pater adest = father is present
• mater et pater adsunt = mother and father are present

The singular form would be adest; the plural form is adsunt.

Yes. adsunt is related to sunt.

It comes from:

• ad- = to, near, at
• sunt = they are

Together, adsunt means something like they are here / they are present / they are at hand.

The dictionary form is adsum, adesse. This is a compound of sum (I am) with the prefix ad-.

So you can think of it like this:

• sum = I am
• sunt = they are
• adsunt = they are present

They are opposites.

• adsunt = they are present
• absunt = they are absent

The second verb comes from:

• ab- = away from
• sunt = they are

So:

• adsum = be present
• absum = be absent

This sentence is neatly contrasting the two:

• Mater et pater adsunt = mother and father are present
• sed ceteri adhuc absunt = but the others are still absent

Ceteri is being used substantively, which means an adjective is standing on its own and functioning like a noun.

Literally, ceteri means the others or the rest. The noun is understood from the context and does not need to be stated.

This is very common in Latin. English does something similar when we say the rich, the poor, or the others.

So here:

• ceteri = the others / the rest

Because ceteri is masculine plural nominative.

In this sentence, it refers to the other people besides mother and father. Latin often uses the masculine plural for a mixed group or for people in general unless there is a reason to specify feminine.

So:

• ceteri = masculine plural, the others
• ceterae = feminine plural, the other women
• cetera = neuter plural, the other things

Since the sentence is about people, ceteri is the natural form.

Adhuc means still, up to this point, or so far.

In this sentence, it modifies absunt:

• adhuc absunt = they are still absent

It adds the idea that the others have not arrived yet. Without adhuc, the sentence would simply say that they are absent. With adhuc, it suggests an ongoing situation.

Sed means but.

It introduces a contrast between the two parts of the sentence:

• Mater et pater adsunt = mother and father are present
• sed ceteri adhuc absunt = but the others are still absent

So sed signals that the second clause differs from or contrasts with the first.

Because Classical Latin has no definite article and no indefinite article. In other words, Latin has no exact words for the or a/an.

Whether you translate a noun with the, a, or no article at all depends on the context.

So:

• mater can mean mother or the mother
• pater can mean father or the father
• ceteri can mean the others

English needs articles more often than Latin does, so translators add them where they make sense.

Yes, Latin word order is more flexible than English word order because the endings show the grammar more clearly.

This sentence uses a very straightforward and natural order:

• subject: Mater et pater
• verb: adsunt
• contrast: sed
• subject: ceteri
• adverb: adhuc
• verb: absunt

But Latin could rearrange the words for emphasis. For example, adhuc ceteri absunt would still be understandable. The chosen order is just clear and uncomplicated.

So the word order here is not strange; it is simply one normal Latin way to say it.

Yes. They are compounds built from sum, which is one of the most important irregular verbs in Latin.

Compare:

• sum = I am
• es = you are
• est = he/she/it is
• sumus = we are
• estis = you all are
• sunt = they are

Now add prefixes:

• adsum = I am present
• ades
• adest
• adsumus
• adestis
• adsunt

And:

• absum = I am absent
• abes
• abest
• absumus
• abestis
• absunt

So a learner who already knows sum can recognize these as related forms.

Here et simply means and. It joins mater and pater into one combined subject:

• mater et pater = mother and father

There is nothing unusual about it in this sentence. It is the ordinary Latin coordinating conjunction and.

Because it joins two nouns, the verb becomes plural: adsunt.