Η δασκάλα είπε «μπράβο» όταν η μαθήτρια διάβασε το κείμενο χωρίς λάθη.

These are definite articles.

• η = feminine singular the
• το = neuter singular the

So:

• η δασκάλα because δασκάλα is feminine
• η μαθήτρια because μαθήτρια is feminine
• το κείμενο because κείμενο is neuter

Greek uses the definite article more often than English, so articles here sound completely natural.

Because the sentence is talking about a female teacher and a female student.

• δασκάλα = female teacher
• μαθήτρια = female student / schoolgirl

If they were male, you would normally have:

• ο δάσκαλος
• ο μαθητής

So the noun endings are giving you gender information.

Yes. είπε is the 3rd person singular aorist form of λέω.

• λέω = I say / I am saying
• είπε = he/she said

This verb is irregular, so a learner cannot guess είπε directly from λέω very easily. It is one of the forms you simply need to learn.

A useful comparison:

• είπα = I said
• είπες = you said
• είπε = he/she said

Yes.

• διαβάζω = I read / I am reading
• διάβασε = he/she read

This is the aorist form, used for a completed action in the past. In this sentence, the student finished reading the text, so διάβασε fits well.

Because the sentence describes two completed events in a story:

• the teacher said μπράβο
• the student read the text

The aorist presents actions as whole, completed events.

If you used the imperfect:

• έλεγε would suggest was saying / used to say
• διάβαζε would suggest was reading / used to read

So the actual sentence sounds like a single finished moment, not an ongoing or repeated one.

Because όταν here refers to a specific event in the past: the moment when the student read the text.

In Greek, after όταν:

• for a specific past event, you often get an indicative past form such as διάβασε
• for repeated past situations, you might get something like διάβαζε
• for future meaning, you often see a subjunctive-type form, for example όταν διαβάσει

So όταν η μαθήτρια διάβασε... means when the student read... in a particular past situation.

It is the direct object of διάβασε, so it is in the accusative case.

However, with many neuter nouns in Modern Greek, the nominative and accusative singular look the same. So:

• nominative: το κείμενο
• accusative: το κείμενο

That is why it does not look different here.

μπράβο is an interjection. It means something like well done or bravo.

It does not change form for gender, number, or case. In other words, it is indeclinable.

In this sentence, it is the exact word the teacher said, so it appears as direct speech.

Those are standard Greek quotation marks.

Greek commonly uses:

• « ... »

instead of English-style quotation marks.

Here they show the exact word spoken by the teacher. You may also see the sentence written without quotation marks in informal writing:

• Η δασκάλα είπε μπράβο...

That is still natural.

χωρίς λάθη means without mistakes in a general sense.

A few useful points:

• χωρίς = without
• λάθη = mistakes, errors

There is no article because the meaning is general, not about specific known mistakes. If you added an article, it would point to particular mistakes:

• χωρίς τα λάθη = without the mistakes

Also, the plural λάθη is natural here because the idea is that there were no mistakes at all.

No. Greek word order is more flexible than English word order.

The given sentence is natural:

• Η δασκάλα είπε μπράβο όταν η μαθήτρια διάβασε το κείμενο χωρίς λάθη.

But you could also say:

• Όταν η μαθήτρια διάβασε το κείμενο χωρίς λάθη, η δασκάλα είπε μπράβο.

The basic meaning stays the same. The difference is mostly about emphasis and flow.

Because the όταν clause comes after the main clause.

That is common in both Greek and English-style punctuation:

• main clause + όταν clause → often no comma before όταν

But if the όταν clause comes first, Greek normally uses a comma after it:

• Όταν η μαθήτρια διάβασε το κείμενο χωρίς λάθη, η δασκάλα είπε μπράβο.

So the punctuation in the original sentence is normal.

In Modern Greek, the written accent mark shows the stressed syllable.

In this sentence:

• δασκάλα → stress on κά
• είπε → stress on εί
• μπράβο → stress on μπρά
• μαθήτρια → stress on θή
• διάβασε → stress on διά
• κείμενο → stress on κεί
• χωρίς → stress on ρίς
• λάθη → stress on λά

That accent mark is very important in Greek, so it is worth paying close attention to it from the beginning.