En caso de que quieras citar la definición exacta, ponla entre comillas.

Because en caso de que normally triggers the subjunctive.

Here, the speaker is talking about a possible situation, not a definite fact: in case you want to cite the exact definition. Since it is hypothetical or uncertain, Spanish uses the subjunctive:

• En caso de que quieras...

If you used quieres, it would sound wrong in standard Spanish in this structure.

A useful pattern to remember is:

• en caso de que + subjunctive

So you get:

• en caso de que vengas
• en caso de que necesites ayuda
• en caso de que quieras citar...

Not exactly.

En caso de que means something like in case or in the event that. It introduces a precaution or possibility.

Si usually means if, and it is often more neutral and direct.

Compare:

• Si quieres citar la definición exacta... = If you want to cite the exact definition...
• En caso de que quieras citar la definición exacta... = In case you want to cite the exact definition...

So en caso de que can sound a bit more formal or more like advice/instructions.

Also, en caso de que is followed by the subjunctive, while si with present meaning normally takes the indicative:

• si quieres
• en caso de que quieras

In standard Spanish, the normal expression is en caso de que.

So the full chunk is:

• en caso de que

It is best to learn it as one fixed expression, not as separate pieces you can freely change.

For a learner, the safest option is always:

• en caso de que + subjunctive

Citar often means to cite, and in many contexts it can also overlap with to quote.

In this sentence, it means something like to cite the exact definition in writing or speech.

A helpful distinction is:

• citar = to cite, mention, quote a source or wording
• poner entre comillas = to put in quotation marks

So the sentence is basically telling you:

• if you are going to cite the exact definition,
• then put it in quotation marks

La refers to la definición exacta.

Since definición is a feminine singular noun, the direct object pronoun is la.

So:

• la definición exacta → la

And ponla is made of:

• pon = informal singular command of poner
• la = it

So ponla means put it.

Because with an affirmative command, object pronouns are attached to the end of the verb in Spanish.

So:

• Ponla = Put it
• Escríbelo = Write it
• Léelo = Read it

But with a negative command, the pronoun goes before the verb:

• No la pongas = Don’t put it
• No lo escribas = Don’t write it
• No lo leas = Don’t read it

So in this sentence, ponla is exactly what you would expect for an affirmative tú command.

Because the sentence is addressing one person informally.

Ponla is the affirmative command for tú from poner.

Other possible versions would be:

• Ponla = informal singular
• Póngala = formal singular
• Ponedla = informal plural in Spain
• Pónganla = formal plural

Since you specified Spanish from Spain, it is especially useful to know the plural informal version:

• Ponedla entre comillas

It means in quotation marks.

Literally:

• entre = between
• comillas = quotation marks

Spanish uses comillas in the plural because quotation marks come as a pair.

This is a very common fixed expression:

• poner algo entre comillas = to put something in quotation marks

In Spain, you may also see different quotation-mark styles in writing, such as angular marks or standard double marks, but the phrase entre comillas works generally for all of them.

Because the sentence begins with a subordinate clause:

• En caso de que quieras citar la definición exacta

Then the main instruction comes after it:

• ponla entre comillas

In Spanish, when this kind of introductory clause comes first, it is very common to separate it from the main clause with a comma. It helps the reader see the structure clearly.

So the sentence is organized like this:

• condition/possibility first
• main command second

Because in Spanish, adjectives usually come after the noun.

So the normal order is:

• la definición exacta

Putting exacta before the noun would sound unusual here and more literary or stylistically marked. In ordinary Spanish, especially in a practical instruction like this one, la definición exacta is the natural choice.

Not with the same meaning.

Citarla means to cite it, but the sentence is specifically telling you what to do with the text formatting: put it in quotation marks.

So:

• citarla = cite it
• ponerla entre comillas = put it in quotation marks

If the exact wording matters, ponerla entre comillas is more precise because it explicitly tells you to mark it as a direct quotation.