Magister dicit se exemplum bonum in tabula scripturum esse.

It is an indirect statement (also called an accusative-and-infinitive construction).

Latin often reports what someone says, thinks, knows, hears, etc. by using:

• a main verb like dicit
• a subject in the accusative
• an infinitive

So here:

• Magister dicit = The teacher says
• se ... scripturum esse = that he will write ...

English usually uses that + a finite verb, but Latin usually uses the accusative + infinitive instead.

Se is the reflexive pronoun. It refers back to the subject of the main verb, here magister.

So:

• Magister dicit se ... scripturum esse = The teacher says that he himself will write ...

If Latin wanted to say that the teacher says someone else will write, it would use a different accusative pronoun, such as eum.

Compare:

• Magister dicit se scripturum esse = The teacher says that he will write
• Magister dicit eum scripturum esse = The teacher says that he / that other man will write

Because in an indirect statement Latin normally uses an infinitive, not a finite verb like scribet.

Here scripturum esse is the future active infinitive of scribo.

It means:

• to be going to write
• to be about to write
• in smoother English here, simply will write

So after dicit, Latin does not usually say:

• Magister dicit se scribet ❌

Instead it says:

• Magister dicit se scripturum esse ✅

It is made of two parts:

• scripturum = the future active participle
• esse = to be

Together they form the future active infinitive.

For scribo, the future participle is based on the stem scriptur-:

• scripturus = about to write, going to write

In indirect statement, that participle agrees with the accusative subject, so here it becomes:

• scripturum because it agrees with se, understood as masculine singular accusative

So literally the phrase is something like:

• to be about-to-write

But in natural English: will write.

Because the future participle must agree with the subject of the infinitive clause, and that subject is se.

Here se refers to magister, so the understood subject is:

• masculine
• singular
• accusative

Therefore the participle is also:

• masculine
• singular
• accusative

So we get scripturum.

If the subject were feminine, you would get:

• scripturam esse

If it were masculine plural:

• scripturos esse

The agreement tells you.

Scripturum is masculine singular accusative, so it agrees with se, not with exemplum.

Now look at exemplum:

• exemplum is neuter singular
• if it were the subject described by the participle, the participle would have to match it
• but scripturum is not neuter, so exemplum cannot be the subject here

That means:

• se = subject of the infinitive clause
• exemplum bonum = object of scribere

This is especially useful because exemplum looks the same in nominative and accusative, so agreement helps you see its role.

Exemplum bonum means a good example.

Grammar:

• exemplum is a neuter singular noun
• bonum is an adjective agreeing with it in gender, number, and case

So both are:

• neuter
• singular
• accusative

They are accusative because exemplum bonum is the direct object of scribere:

• he will write what?
• a good example

Here in tabula means on the board or on the tablet/surface, depending on context. In a classroom sentence like this, it is very natural to understand tabula as the board.

The case is important:

• in
  • ablative usually indicates location
• in
  • accusative usually indicates motion toward/into

So:

• in tabula = on/in the board as the place where the writing happens
• in tabulam would suggest movement onto or into something

Since the teacher is writing on the board, not moving something onto it, the ablative is used.

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

The sentence is:

• Magister dicit se exemplum bonum in tabula scripturum esse.

A very literal rearrangement into English-style order would be:

• The teacher says that he will write a good example on the board.

Latin often places the infinitive phrase toward the end, so scripturum esse comes last.

You could also rearrange the Latin without changing the basic meaning very much, for example:

• Magister se exemplum bonum in tabula scripturum esse dicit.

That is still correct Latin. The difference is mainly one of emphasis and style, not core meaning.

In standard prose, esse is part of the future infinitive and is normally included.

The future infinitive is:

• future participle + esse

So:

• scripturum esse = to be about to write / will write

Without esse, scripturum by itself is just a participle, not the full infinitive form needed here.

In some poetic or highly compressed Latin, forms of esse can be omitted, but for normal prose and for learners, you should treat scripturum esse as the proper complete form.

It is future relative to the time of the saying.

So:

• Magister dicit se ... scripturum esse = The teacher says that he will write ...

If you changed the main verb to past:

• Magister dixit se ... scripturum esse

that would mean:

• The teacher said that he would write ...

So the future infinitive does not just mean future in an absolute sense. It means future with respect to the main verb of saying/thinking/etc.