Servae mēnsam in trīclīniō ad cēnam instruunt.

Because the verb instruunt is third person plural, so it needs a plural subject: they prepare / they arrange.

The form servae can be ambiguous by itself, because it could be:

• nominative plural = the female slaves / maidservants
• genitive singular = of the female slave
• dative singular = to/for the female slave

But in this sentence, the plural verb instruunt shows that servae must be nominative plural, so it is the subject.

Because mēnsam is the direct object of instruunt.

The verb instruere here means something like to set out, arrange, prepare, and the thing being prepared is the table. In Latin, a direct object usually goes in the accusative case.

So:

• mēnsa = table, nominative singular
• mēnsam = table, accusative singular

That is why Latin uses mēnsam rather than mēnsa.

Because in can take different cases depending on meaning.

• in + ablative = in / on in the sense of location
• in + accusative = into / onto in the sense of motion toward

Here the sentence is saying where the table is being prepared: in the dining room. That is location, so Latin uses the ablative:

• trīclīnium = nominative/accusative singular
• trīclīniō = ablative singular

So in trīclīniō means in the dining room.

Literally, ad often means to or toward, but with expressions like this it can also show purpose or occasion.

So ad cēnam means:

• for dinner
• for the meal
• more literally, for/at dinner time

Here it tells us the purpose of preparing the table: they are setting it out for dinner.

Also notice that ad takes the accusative case, so cēnam is accusative.

Instruunt is:

• present tense
• active voice
• indicative mood
• third person plural

It comes from instruere, a third-conjugation verb.

So instruunt means they prepare, they arrange, or they set out.

The ending -unt is a very common sign of a third-person plural present verb in the third conjugation.

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

In English, word order usually tells you what each word is doing:

• The slaves prepare the table

In Latin, the endings usually tell you that instead:

• servae = subject
• mēnsam = direct object
• trīclīniō = place
• cēnam = object of ad
• instruunt = plural verb

Since the grammar is shown by endings, Latin can move words around more freely. Putting the verb at the end is very common and often sounds natural in Latin prose.

Yes, often they could.

For example, these would still basically mean the same thing:

• Servae mēnsam in trīclīniō ad cēnam instruunt.
• In trīclīniō servae mēnsam ad cēnam instruunt.
• Mēnsam servae ad cēnam in trīclīniō instruunt.

The endings keep the basic roles clear.

However, changing the order can change the emphasis. Latin word order is often used to highlight a particular word, even when the core meaning stays the same.

A trīclīnium is a Roman dining room.

More specifically, in Roman culture it was a dining area associated with couches for reclining while eating. So when you read in trīclīniō, it does not just mean any room; it refers to a specifically Roman dining setting.

That cultural detail is useful, because the sentence is not just about any table in any house, but about preparing for a Roman meal.

Strictly speaking, servae is the plural of serva, which most literally means female slaves.

Depending on context, English translations may soften this to servants or maidservants, especially in beginner materials. But the basic Latin word is tied to slavery, not free employment in the modern sense.

So if you want the most literal sense, servae = female slaves.

They matter for learning, even though many Latin texts leave them out.

Macrons show vowel length:

• mēnsam
• trīclīniō
• cēnam

Why this helps:

• it improves pronunciation
• it helps with meter in poetry
• it sometimes helps distinguish forms that would otherwise look the same
• it can make vocabulary learning easier

For example, a student who learns trīclīniō with the macron is more likely to remember the correct vowel length.

So yes, macrons are useful, even if you will often see the sentence printed without them.