Η δασκάλα μάς ζήτησε να βρούμε το αντίθετο αυτής της λέξης.

Η is the definite article, so η δασκάλα means the teacher.

It also shows gender and case:

• η = feminine singular nominative
• δασκάλα = feminine singular noun

So η δασκάλα is the subject of the sentence: the female teacher.

If the teacher were male, you would normally have:

• ο δάσκαλος = the male teacher

μάς means us.

It is the weak object pronoun, and in Greek these short pronouns usually come before a finite verb:

• μας ζήτησε = asked us

That is normal Greek word order for object pronouns.

The accent in μάς is often written for clarity, especially to help distinguish it from possessive μας meaning our, although in many contexts you may also see it written without the accent.

ζήτησε is the aorist form, 3rd person singular, of ζητώ / ζητάω.

Here it means:

• she asked
• she requested

So:

• η δασκάλα μάς ζήτησε = the teacher asked us

A few useful contrasts:

• ζητάει / ζητεί = she asks / is asking
• ζητούσε = she was asking / used to ask
• ζήτησε = she asked

Greek normally uses να + a verb form where English often uses an infinitive or a clause like to...

So instead of something like asked us to find, Greek says:

• μας ζήτησε να βρούμε

Literally, this is closer to:

• asked us that we find

But in natural English, it is simply:

• asked us to find

This is a very common Greek pattern after verbs like:

• θέλω να... = I want to...
• μπορώ να... = I can...
• ζήτησε να... = she asked to / asked that...

βρούμε is the aorist subjunctive form of βρίσκω after να.

Greek often chooses between:

• να βρούμε = to find, as a single completed action
• να βρίσκουμε = to be finding / to find repeatedly or habitually

Here the teacher asked for one completed result: find the opposite of the word. So να βρούμε is the natural choice.

So:

• να βρούμε το αντίθετο = to find the opposite

Because βρούμε is the 1st person plural form:

• βρω = I find
• βρεις = you find
• βρει = he/she/it finds
• βρούμε = we find
• βρείτε = you (plural) find
• βρουν(ε) = they find

In this sentence, μάς already tells you that we/us are involved, so να βρούμε fits perfectly: for us to find.

αντίθετο is originally an adjective meaning opposite, but here it is being used as a noun:

• το αντίθετο = the opposite

This is very common in Greek: an adjective with the article can function like a noun.

Examples:

• το καλό = the good
• το κακό = the bad
• το αντίθετο = the opposite

So το αντίθετο αυτής της λέξης means the opposite of this word.

Because this part means of this word, and Greek expresses that with the genitive.

Base form:

• αυτή η λέξη = this word

Genitive form:

• αυτής της λέξης = of this word

Both the demonstrative and the noun change because both belong to the same noun phrase.

You can think of it like this:

• nominative: αυτή η λέξη
• genitive: αυτής της λέξης

So:

• το αντίθετο αυτής της λέξης = the opposite of this word

That is simply how Greek normally builds a phrase with a demonstrative plus noun.

In the nominative:

• αυτή η λέξη = this word

In the genitive:

• αυτής της λέξης = of this word

So Greek keeps:

1. the demonstrative (this)
2. the article (the)
3. the noun (word)

This is a very normal pattern:

• αυτό το βιβλίο = this book
• αυτού του βιβλίου = of this book

The basic form is:

• λέξη = word

Here it appears in the genitive singular:

• της λέξης = of the word

So the forms are:

• η λέξη = the word
• της λέξης = of the word

This is a common pattern for feminine nouns in -η.

Yes. Greek word order is more flexible than English.

The given sentence is very natural:

• Η δασκάλα μάς ζήτησε να βρούμε το αντίθετο αυτής της λέξης.

But you could also hear:

• Η δασκάλα ζήτησε να βρούμε το αντίθετο αυτής της λέξης.
• Μας ζήτησε η δασκάλα να βρούμε το αντίθετο αυτής της λέξης.

The meaning stays basically the same, but the emphasis changes a little.

The original version is neutral and clear:

• subject first: Η δασκάλα
• object pronoun before the verb: μάς ζήτησε

Yes.

• ζητώ / ζητάω often means ask for, request, or demand
• ρωτώ / ρωτάω more often means ask in the sense of putting a question

In this sentence, the teacher is not just asking a question; she is assigning or requesting an action. So ζήτησε να βρούμε... is very appropriate.

Compare:

• Μας ρώτησε ποιο είναι το αντίθετο. = She asked us what the opposite is.
• Μας ζήτησε να βρούμε το αντίθετο. = She asked us to find the opposite.