Είχες να μιλήσεις με τον πεθερό σου πολύ καιρό ή τον βλέπεις συχνά;

Here είχες να μιλήσεις is not a literal you had to speak. It is the Greek pattern έχω να + verb, which often means it has been ... since someone did something.

So Είχες να μιλήσεις με τον πεθερό σου πολύ καιρό; means something like:

• Had it been a long time since you had talked to your father-in-law?
• or more naturally in English, Had you not talked to your father-in-law for a long time?

It is a very common Greek way to talk about how much time has passed since the last occurrence of something.

Yes. Even though Greek does not use δεν here, the whole expression implies non-occurrence during that period.

For example:

• Έχω να τον δω δύο μήνες. = I haven’t seen him for two months.
• Είχα να πάω εκεί χρόνια. = I hadn’t gone there for years.

So είχες να μιλήσεις ... πολύ καιρό carries the idea you had not spoken ... for a long time.

Because Modern Greek normally uses να + verb form where English often uses an infinitive or another clause structure.

Greek does not use the old infinitive as a normal everyday form, so instead of something like to speak, Greek says να μιλήσεις.

In this sentence, να is part of the fixed pattern έχω να + verb.

Because Greek is choosing the aorist aspect here: να μιλήσεις.

That usually points to a single completed event, or at least to the event as a whole. In this sentence, the speaker is talking about the last time you spoke with him, not about an ongoing activity.

• να μιλήσεις = to speak / have that conversation
• να μιλάς = to be speaking / to speak repeatedly or continuously

With έχω να + verb plus a time expression, the aorist is very common because the focus is on the gap since the last completed event.

Because the speaker is viewing the situation from a past point of reference.

• έχεις να μιλήσεις = it has been a while since you spoke
• είχες να μιλήσεις = it had been a while since you had spoken

So the imperfect είχες sets the whole expression in the past. It describes a past state: at that time, there had been a long gap since the last conversation.

Yes, in some contexts έχω να + verb can be understood more like I have to / I still need to.

But here the time expression πολύ καιρό makes the temporal meaning clear.

Compare:

• Έχω να γράψω μια αναφορά. = I have a report to write / I need to write a report.
• Έχω να γράψω τρεις μέρες. = I haven’t written for three days.

In your sentence, because of πολύ καιρό, the meaning is definitely it had been a long time since...

Because Greek normally uses the definite article with possessed nouns.

So Greek says:

• ο πατέρας μου = my father
• η αδερφή σου = your sister
• τον πεθερό σου = your father-in-law

This is normal Greek structure. English usually drops the article in these cases, but Greek keeps it.

The dictionary form is ο πεθερός.

Here it becomes τον πεθερό because:

1. it is after με, and με takes the accusative
2. masculine singular accusative uses τον
3. the noun changes from πεθερός to πεθερό

So:

• nominative: ο πεθερός
• accusative: τον πεθερό

Πεθερός means father-in-law.

Related words:

• πεθερά = mother-in-law
• γαμπρός = son-in-law / groom
• νύφη = daughter-in-law / bride

In this sentence, τον πεθερό σου means your father-in-law.

Yes, both are possible, but the nuance is slightly different.

• μιλάω με κάποιον = I talk with someone / have a conversation with someone
• μιλάω σε κάποιον = I talk to someone / address someone

So να μιλήσεις με τον πεθερό σου suggests an interaction or conversation with him.
If you said να μιλήσεις στον πεθερό σου, it would sound more like talking to him, possibly more one-directional.

Here πολύ καιρό means for a long time or, in natural English with this structure, in a long time.

In the έχω να + verb pattern, Greek often puts the time expression directly after the verb phrase:

• Έχω να τον δω πολύ καιρό.
• Έχει να έρθει μήνες.
• Είχα να το κάνω χρόνια.

So no για is needed here. The phrase is functioning as the amount of elapsed time since the last event.

Τον is the direct-object pronoun him.

It refers back to τον πεθερό σου. So:

• τον βλέπεις = you see him

Greek uses these short object pronouns very often. Once the noun has already been mentioned, using τον is the normal way to refer back to it.

Because the speaker is contrasting two different ideas:

1. Had it been a long time since you had talked to him?
2. Or do you see him often?

The second clause asks about your usual or current habit, so the present βλέπεις is natural.

If the speaker wanted both parts to stay in the past, Greek could say something like:

• ...ή τον έβλεπες συχνά; = ...or did you see him often?

Συχνά means often / frequently.

So τον βλέπεις συχνά means:

• you see him often
• you see him frequently

It usually comes after the verb, but Greek word order is flexible.

Yes. Greek word order is fairly flexible, especially with adverbs and time expressions.

You could also hear:

• Είχες πολύ καιρό να μιλήσεις με τον πεθερό σου;
• Με τον πεθερό σου είχες να μιλήσεις πολύ καιρό;

The original sentence is completely natural. The different orders mainly change emphasis, not the core meaning.