Magister eos laudat, qui veritatem dicunt.

• Magister = the teacher
• eos = them / those people
• laudat = praises
• qui = who
• veritatem = the truth
• dicunt = say / speak

So the structure is:

• Magister = subject
• eos = direct object of laudat
• qui veritatem dicunt = a relative clause describing eos

In other words, the teacher praises those who tell the truth.

Because Latin is using a very common pattern:

• eos ... qui ... = those ... who ...

Here, eos points out the people, and qui veritatem dicunt tells you which people.

So:

• eos = those people
• qui veritatem dicunt = who tell the truth

Together, they mean those who tell the truth.

English often does the same thing:

• I praise those who work hard.

Latin is just doing it very explicitly.

This is one of the most important things to understand about Latin relative pronouns.

Qui refers back to eos, but its case is determined by its job inside the relative clause, not by the case of eos.

Here:

• eos is accusative because it is the object of laudat
• qui is nominative because it is the subject of dicunt

Inside the relative clause, the people are the ones doing the speaking, so Latin uses the nominative:

• qui veritatem dicunt = who tell the truth

If it were quos, that would make who/whom the object inside the relative clause, which is not what is happening here.

A useful rule:

• A relative pronoun agrees with its antecedent in gender and number
• But its case depends on its role in its own clause

So:

• antecedent: eos = masculine plural
• relative pronoun: qui = masculine plural too
• but nominative, because it is the subject of dicunt

Because they have different subjects.

• laudat goes with magister = the teacher praises
• dicunt goes with qui = who tell

So:

• magister laudat = one teacher, so singular verb
• qui dicunt = several people, so plural verb

This is very normal in sentences with relative clauses. Each clause has its own subject and verb.

Veritatem is accusative singular.

That is because it is the direct object of dicunt:

• dicunt veritatem = they tell the truth

The dictionary form is veritas (truth), and its accusative singular is veritatem.

So the clause works like this:

• qui = subject
• dicunt = verb
• veritatem = direct object

Because magister is in the nominative singular, which is the normal case for the subject.

Also, the verb laudat is third person singular, which matches magister:

• magister = one teacher
• laudat = he/she/it praises

So magister is the one doing the praising.

Meanwhile, eos is accusative plural, so it cannot be the subject of laudat here; it is the object.

The word order is helpful, but the endings matter more than the position.

Latin is more flexible than English because case endings show each word’s job.

So in this sentence:

• magister is still the subject because it is nominative
• eos is still the object because it is accusative
• qui is still the subject of dicunt because it is nominative

That means Latin could rearrange the sentence for emphasis more easily than English.

This order is fairly straightforward and natural:

• main clause first: Magister eos laudat
• then the relative clause: qui veritatem dicunt

It is a relative clause modifying eos.

Its job is to identify which people the teacher praises.

Without the relative clause:

• Magister eos laudat = The teacher praises them

With the relative clause:

• Magister eos laudat, qui veritatem dicunt = The teacher praises those who tell the truth

So the relative clause narrows down or explains who eos refers to.

Sometimes Latin can omit an expressed antecedent, but eos qui ... is a very common and clear way to say those who ...

So here, eos is not unnecessary; it is part of a standard Latin pattern.

You can think of it as:

• eos qui veritatem dicunt = those who tell the truth

For a learner, it is often easiest to recognize this whole phrase as a unit.

The comma is a matter of modern editorial punctuation, not something ancient Latin writers originally depended on in the same way English does.

It helps modern readers see that qui veritatem dicunt is a separate clause attached to eos.

So the comma is useful for reading, but the grammar does not depend on it. The endings already show how the sentence works.

Here qui is:

• relative pronoun
• masculine
• plural
• nominative

Why?

• masculine plural because it refers back to eos
• nominative because it is the subject of dicunt

So this is a textbook example of the rule:

• relative pronoun agrees with its antecedent in gender and number
• takes its case from its own function in the relative clause