Pater in tablino manet, dum mater in triclinio mensam instruit et convivas exspectat.

Because in with a fixed location takes the ablative in Latin.

• in tablino = in the study/office
• in triclinio = in the dining room

If in meant motion into a place, it would usually take the accusative instead.

• in triclinio = in the dining room (location)
• in triclinium = into the dining room (motion)

So here the father and mother are already in those rooms, which is why the ablative is used.

These are names for rooms in a Roman house.

• tablinum = a study, office, or formal room used by the head of the household
• triclinium = a dining room

In the sentence, their forms are ablative singular:

• tablino < tablinum
• triclinio < triclinium

A learner may notice that these are not common English-style household words; they are specifically Roman cultural vocabulary.

Because mensam is the direct object of instruit.

The verb instruere can mean to equip, arrange, prepare, set out. Here it means something like set/prepare the table.

So:

• mater ... mensam instruit = the mother prepares/sets the table

Since the table is the thing being prepared, it goes into the accusative:

• nominative: mensa
• accusative: mensam

Literally, instruit comes from instruere, which often means to arrange, equip, or prepare.

With mensam, it means something like:

• sets the table
• lays the table
• prepares the table

So this is not just looks at the table or moves the table. It suggests getting it ready for a meal.

Because convivas is the direct object of exspectat.

• exspectat = waits for / expects
• convivas = guests

So:

• mater convivas exspectat = the mother is waiting for the guests

convivas is the accusative plural of conviva.

Here dum means while.

So the sentence is contrasting or linking two actions happening at the same time:

• Pater in tablino manet
• dum mater in triclinio mensam instruit et convivas exspectat

That gives the sense: Father stays in the study while mother sets the table in the dining room and waits for the guests.

In other contexts, dum can also mean until, so learners often need to decide from context which meaning fits.

Each verb agrees with its own subject.

• Pater ... manet → pater is singular, so manet is singular
• mater ... instruit et ... exspectat → mater is singular, so both instruit and exspectat are singular

All three verbs are third person singular present active indicative.

Latin normally has no articles.

So Latin can say:

• pater = father / the father / a father
• mater = mother / the mother / a mother
• mensam = table / the table / a table

English has to choose an article when translating, but Latin usually leaves that to context.

Latin word order is more flexible than English word order because endings show the grammatical roles.

This sentence could not be translated word-for-word into natural English order:

• Pater in tablino manet = Father remains in the study
• dum mater in triclinio mensam instruit et convivas exspectat = while mother in the dining room sets the table and waits for the guests

A few things to notice:

• The subjects pater and mater come early.
• The verbs often come later, especially in the second clause.
• convivas comes before exspectat, even though in English we would usually say waits for the guests.

So the endings matter more than the position.

Because some Latin verbs take a direct object where English uses a verb plus a preposition.

• Latin: convivas exspectat
• English: she waits for the guests

So the idea of for is built into how English expresses the verb, but Latin simply uses exspectare + accusative.

This is very common in language learning: Latin and English do not always package meaning in the same way.

Either can work, depending on context.

manet comes from manere, meaning to remain, to stay, or to continue to be somewhere.

In this sentence:

• Pater in tablino manet

could be translated as:

• Father remains in the study
• Father stays in the study

Remains is a bit more literal; stays is often more natural in everyday English.

Because instruit and exspectat share the same subject, mater.

So:

• mater ... mensam instruit et convivas exspectat

means:

• the mother sets the table and waits for the guests

Latin does not need to repeat mater before the second verb, just as English usually would not repeat the mother in the same situation.