Mater puerum e via revocat, ne diu foris moretur.

Because of the case endings.

• mater is nominative singular, so it is the subject: the mother
• puerum is accusative singular, so it is the direct object: the boy

So Latin shows their roles by form, not mainly by word order. Even if the words were rearranged, the endings would still tell you who is doing the action and who is receiving it.

Revocat comes from revoco, revocare and literally means calls back.

The prefix re- adds the idea of back or again, so revocat is stronger than just vocat. It suggests that the boy is being called back from where he is.

Depending on context, it can be translated as:

• calls back
• summons back
• calls away from
• sometimes more loosely, brings back

After e/ex, Latin uses the ablative case. So via here is ablative singular.

• e/ex = out of, from
• via = road, street, way
• e via = from the road/street or off the road

So the phrase shows the place from which the boy is being called back.

Both e and ex mean the same thing here: out of or from.

In many textbooks you will learn that:

• ex is common before vowels
• e is common before consonants

But actual Latin usage is not completely rigid, and both forms are normal. In e via, e is perfectly standard.

Because this is a negative purpose clause.

Latin uses:

• ut
  • subjunctive for a positive purpose: so that
• ne
  • subjunctive for a negative purpose: so that not, lest

So ne diu foris moretur means something like:

• so that he may not stay outside long
• lest he linger outside for a long time

Non normally negates a word or a statement, but it is not the normal way to make a purpose clause negative.

Because ne diu foris moretur is a purpose clause, and purpose clauses in Latin take the subjunctive.

The main clause is Mater puerum e via revocat. Then Latin adds the reason or aim of that action:

• she calls him back
• so that he may not linger outside long

That idea of purpose/aim is what triggers the subjunctive.

Also, since the main verb revocat is present, Latin uses the present subjunctive moretur. If the main verb were past, you would often expect the imperfect subjunctive instead, such as moraretur.

Because moror, morari is a deponent verb.

Deponent verbs:

• have passive-looking forms
• but active meanings

So moretur looks like a passive form, but it means he may linger, he may delay, or he may stay, not he may be lingered or anything like that.

This is very common in Latin, and learners usually just have to get used to recognizing deponent verbs.

Foris means outside, outdoors, in the sense of location.

That is different from foras, which usually means outward or to the outside, expressing motion toward the outside.

A useful contrast is:

• foris = outside (where?)
• foras = outside/out doors (to where?)

Since morari means to stay or linger, it needs a word of location, not motion. So foris is the right choice.

Diu is an adverb meaning for a long time or long.

It modifies moretur:

• diu moretur = linger for a long time

So ne diu foris moretur means so that he may not stay outside for long.

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

This sentence is arranged in a very natural Latin way:

• Mater first: the topic or subject
• puerum early: the person affected
• e via revocat: the main action
• ne diu foris moretur at the end: the purpose clause

In English, word order does much more grammatical work. In Latin, word order is often used more for emphasis, rhythm, and style.

Because Classical Latin has no articles.

So a noun like mater can mean:

• mother
• a mother
• the mother

and puerum can mean:

• a boy
• the boy

The context tells you which English article makes best sense. In this sentence, English naturally uses the mother and the boy, but Latin does not need separate words for that.