En clase leímos el monólogo en voz alta y luego hablamos de si el diálogo parecía real.

In Spanish, en clase is a very common fixed expression meaning in class / during class in a general sense.

• En clase = in class, during class
• En la clase = in the class, in a specific classroom session or class

So here, En clase leímos... means During class, we read...

If you said en la clase, it would sound more specific, as if you meant a particular class that has already been identified.

They are in the preterite because they describe completed actions in the past:

• leímos = we read
• hablamos = we talked

The sentence presents a sequence of events:

1. we read
2. then we talked

That kind of finished, ordered narration is exactly what the preterite is often used for in Spanish.

If the sentence used the imperfect instead, it would sound more like background information or an ongoing repeated situation, which is not the idea here.

Parecía is in the imperfect because it describes how something seemed, not a single completed event.

Here, the sentence is about a judgement or impression:

• si el diálogo parecía real = whether the dialogue seemed real

Spanish often uses the imperfect for:

• descriptions
• background information
• mental impressions
• what something was like

So:

• parecía real = it seemed real
• pareció real = it seemed real at a specific moment / it came across as real

In this sentence, the imperfect sounds more natural because the speakers are discussing the general impression of the dialogue.

Here si means whether, not if in the conditional sense.

• hablar de si... = to talk about whether...

So:

• hablamos de si el diálogo parecía real
• we talked about whether the dialogue seemed real

After verbs like hablar de, preguntar, dudar, discutir, Spanish often uses si to introduce an indirect yes/no question.

A useful comparison:

• No sé si viene. = I don’t know whether he’s coming.
• Hablamos de si parecía real. = We talked about whether it seemed real.

Also, this is si without an accent.

• si = if / whether
• sí = yes

En voz alta is a fixed expression meaning out loud / aloud.

Literally, it is something like:

• en = in
• voz = voice
• alta = high/loud

But you should learn it as one chunk: en voz alta = aloud

Examples:

• Leer en voz alta = to read aloud
• Decir algo en voz alta = to say something out loud

Spanish normally does not use an article here, so en la voz alta would be wrong.

Yes, they refer to different things:

• monólogo = monologue, a speech by one person
• diálogo = dialogue, conversation between two or more people

The sentence may be talking about two different parts of a class activity:

• first, they read the monologue aloud
• then, they discussed whether the dialogue sounded real

Grammatically, both are masculine nouns:

• el monólogo
• el diálogo

Even though they end in -o, that is normal for masculine nouns.

The accents show stress and sometimes help separate vowels.

leímos

The accent on í shows that e and í are pronounced in separate syllables:

• le-í-mos

Without the accent, Spanish pronunciation rules would suggest a different syllable pattern.

monólogo and diálogo

These accents show where the stress falls:

• mo-NÓ-lo-go
• di-Á-lo-go

Spanish spelling uses written accents when a word’s stress does not follow the default stress rules.

Spanish often leaves out subject pronouns because the verb ending already shows who the subject is.

• leímos = we read
• hablamos = we talked

So nosotros is unnecessary unless you want emphasis or contrast.

For example:

• Leímos el monólogo. = We read the monologue.
• Nosotros leímos el monólogo, no ellos. = We read the monologue, not them.

In your sentence, no emphasis is needed, so leaving out nosotros is the most natural choice.

Both are possible, but luego hablamos is more natural here because luego helps organise the sequence of events:

• En clase leímos... y luego hablamos...
• In class we read..., and then we talked...

Putting luego before the verb makes the timeline especially clear. Spanish is fairly flexible with word order, but this placement is very common in narration.

Pretty much, yes. In this sentence:

• el diálogo parecía real = the dialogue seemed real

Here real means:

• natural
• believable
• authentic-seeming

So it does not necessarily mean factually true. It means the dialogue sounded like something real people would actually say.

That is a very common use in both Spanish and English when talking about writing, acting, or conversation.

You may hear hablar sobre in some contexts, but with this structure hablar de si... is the most natural and standard choice.

• hablar de algo = to talk about something
• hablar de si... = to talk about whether...

So:

• Hablamos de si el diálogo parecía real sounds natural.
• Hablamos sobre si... is much less common and may sound awkward to many speakers.

For learners, it is safest to remember:

• hablar de + noun / clause

Example:

• Hablamos del texto. = We talked about the text.
• Hablamos de si era realista. = We talked about whether it was realistic.