Risus pueri matrem laetam facit.

Because pueri can be more than one thing:

• genitive singular = of the boy
• nominative plural = boys

In this sentence, the verb is facit, which is singular: he/she/it makes. So the subject must also be singular. That makes risus the subject, not pueri.

So here pueri is best understood as genitive singular: the boy’s.

Here risus is nominative singular, so it is the subject of facit.

It comes from the 4th-declension noun risus, risus meaning laughter or smile. In the nominative singular, the form is risus.

So:

• risus = the laughter / laughter
• subject of facit

Because matrem is the direct object of facit.

The verb facere often means to make, and in a sentence like this it can take:

• a thing/person being affected in the accusative
• plus a word describing what that person becomes

So:

• matrem = mother in the accusative
• it is the person being made happy

Because laetam agrees with matrem.

Both are:

• accusative
• singular
• feminine

This is because laetam is describing the result affecting matrem: makes the mother happy.

This is a very common Latin pattern with verbs like facere:

• aliquem laetum facere = to make someone happy
• aliquem timidum facere = to make someone fearful

So laetam is not describing risus. It goes with matrem.

Not exactly in sense, even though the words agree.

Grammatically, matrem laetam could look like the happy mother, but with facit the natural meaning is makes the mother happy, not simply makes the happy mother.

So laetam is functioning as a complement to the object, telling you what the mother is made to be.

A helpful way to think of it is:

• matrem = the person affected
• laetam = the state she is brought into

Latin word order is much freer than English word order because Latin shows grammatical function mainly through endings, not position.

So in this sentence:

• risus = subject
• pueri = genitive
• matrem = object
• laetam = adjective agreeing with matrem
• facit = verb

Even though English would usually say something like The boy’s laughter makes the mother happy, Latin can arrange the words differently without changing the core meaning.

Latin often places the verb near the end, and related words do not always have to stand next to each other.

In form, yes; in this sentence, no.

Pueri can be:

• genitive singular = of the boy
• nominative plural = the boys

But if pueri were the subject, the verb would normally be plural: faciunt, not facit.

Since the verb is singular, pueri is understood as of the boy.

Pueri depends on risus as a genitive.

So:

• risus pueri = the boy’s laughter
• literally, laughter of the boy

This is a very common Latin way to show possession or close relationship.

Because its subject is risus, which is singular.

The sentence is not saying the boys make; it is saying the laughter makes.

So:

• risus = singular subject
• facit = singular verb

That agreement helps you identify the structure of the sentence.

You would look them up like this:

• risus → risus, risus = laughter, smile
• pueri → puer, pueri = boy
• matrem → mater, matris = mother
• laetam → laetus, laeta, laetum = happy, glad
• facit → facio, facere, feci, factum = make, do

This is useful because several of the forms in the sentence are not the basic form you would see in a dictionary.

Usually laughter is the safer choice here, especially in a sentence like this.

Risus can mean:

• laughter
• sometimes smile

If the given meaning already shows The boy’s laughter makes the mother happy, that fits the grammar very naturally.

The pattern is:

subject + genitive + object + object complement + verb

More specifically:

• risus = subject
• pueri = dependent genitive
• matrem = direct object
• laetam = adjective complementing the object
• facit = verb

So the core structure is:

X makes Y happy

In Latin:

X Y happy makes or in this exact sentence: The boy’s laughter makes the mother happy