Puer currens matrem vocat.

Because puer is in the nominative singular, which is the case normally used for the subject in Latin.

So in this sentence:

• puer = the boy
• vocat = calls

That gives the boy calls.

Latin often shows who is doing the action through case endings, not just word order.

Because matrem is in the accusative singular, which is the case used for the direct object.

Here, the mother is the person being called, not the one doing the calling.

So:

• mater = mother as a subject
• matrem = mother as a direct object

That is why Latin uses matrem vocat for calls mother / calls his mother.

Currens is a present participle. It means running.

A participle is a verbal adjective, so it has qualities of both:

• a verb: it comes from currere, meaning to run
• an adjective: it describes a noun

Here it describes puer, so the sense is:

• the running boy calls his mother
• or more naturally in English, the boy, running, calls his mother
• or the boy calls his mother while running

Because currens agrees with puer in case, number, and gender.

Here:

• puer is nominative singular masculine
• currens is nominative singular, matching the subject

But matrem is accusative singular, so currens does not match it.

That tells us the boy is the one running, not the mother.

Because currens belongs to a different kind of word.

It is a third-declension participle, not a second-declension noun like puer. Latin words do not have to look alike to agree; they just have to have matching grammatical features.

So even though:

• puer does not end in -s
• currens does end in -s

they can still agree because both are nominative singular and refer to the same person.

It can suggest both at once.

A Latin present participle often combines these ideas:

• describing the noun: the running boy
• showing an ongoing action: the boy, while running

So in this sentence, English could translate the idea in more than one natural way:

• The running boy calls his mother
• The boy calls his mother while running
• The boy, running, calls his mother

Latin leaves that slightly flexible.

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

So Puer currens matrem vocat is a normal Latin order, with the verb at the end. But Latin could also move the words around for emphasis, for example:

• Puer matrem currens vocat
• Matrem puer currens vocat

The basic meaning would still stay the same because:

• puer is nominative
• matrem is accusative
• vocat is the verb

Putting the verb last is very common in Latin.

Classical Latin has no articles like English the or a.

So puer can mean:

• the boy
• a boy

and matrem can mean:

• the mother
• a mother

Which one is best depends on context. In many teaching sentences, English uses the because it sounds more natural.

Latin often leaves possession unstated when it is obvious from context.

So matrem vocat literally means calls mother, but natural English usually says calls his mother.

Latin does have possessive words such as suam, but they are not always necessary. If the mother obviously belongs to the subject, Latin may simply use matrem.

Vocat is:

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

from the verb vocare, meaning to call.

So vocat means:

• he calls
• she calls
• it calls

In this sentence, since the subject is puer, it means the boy calls.

Yes. Because Latin participles and article-less nouns can be flexible, several English translations are possible.

Some good possibilities are:

• The running boy calls his mother
• The boy who is running calls his mother
• The boy calls his mother while running

These are slightly different in style, but they all reflect the same basic Latin structure.