Learn Hardcore Greek: Η πόρτα που ανοίγεις δεν κλείνει καλά. - The door that you are opening doesn't close well.

που introduces a defining relative clause, equivalent to English that/which/who. Here it links η πόρτα to the clause ανοίγεις: “the door that you (are) opening.” It is invariable (no gender/case/number changes), and the “gap” it creates is the direct object of ανοίγεις inside the relative clause.

Why isn’t there a comma before που?

Because this is a defining (restrictive) relative clause: it specifies which door we mean. Greek does not use a comma before που in such clauses. With a non-defining clause you would normally prefer the inflected relative η οποία and set it off with commas: Η πόρτα, την οποία ανοίγεις, …

Should που have an accent (as πού) here?

No. πού (with accent) means “where?” (interrogative). που (without accent) is the relative/complementizer “that/which/who.” In this sentence it must be the unaccented που.

Why is there no εσύ (“you”) before ανοίγεις?

Modern Greek is a “pro‑drop” language: subject pronouns are usually omitted because the verb ending shows the person/number. ανοίγεις ends in ‑εις, which already tells us “you (sg) open/are opening.”

How do the verb endings show who is doing the action here?

ανοίγω = I open; ανοίγεις = you (sg) open
κλείνω = I close; κλείνει = he/she/it closes

So ανοίγεις is 2nd person singular; κλείνει is 3rd person singular, agreeing with η πόρτα as the subject of the main clause.

Why is the negation δεν and not μην?

Use δεν to negate the indicative (statements/facts): δεν κλείνει = “it doesn’t close.” Use μην with the subjunctive or negative imperatives: μην την κλείνεις = “don’t close it.”

Is δε also correct?

In casual speech, δεν can be pronounced (and sometimes written) as δε before many consonants. In careful writing, δεν is the safe default. Before κλείνει, both are heard; you’ll most often see δεν in print.

Why καλά and not καλώς or καλό?

καλά is the adverb “well/properly” and is what you want after a verb: κλείνει καλά.
καλώς is a more formal/literary adverb, mostly in set phrases (e.g., Καλώς ήρθες).
καλό is the adjective “good” (neuter), not used to modify verbs.

Can καλά go somewhere else in the sentence?

The neutral position is after the verb: δεν κλείνει καλά. Fronting it (Καλά δεν κλείνει) is possible but adds emphasis/contrast. You can also expand it: δεν κλείνει καθόλου καλά (“not at all well”).

Can I say Η πόρτα που την ανοίγεις with a clitic την?

In standard usage, when the relativized element is a direct object, you normally do not add a resumptive clitic: Η πόρτα που ανοίγεις is preferred. Forms like που την ανοίγεις occur in colloquial speech and some dialects but are best avoided in careful writing.

Can I replace που with την οποία?

Yes, for a more formal tone and explicit case marking: Η πόρτα την οποία ανοίγεις δεν κλείνει καλά. Here την οποία is feminine accusative singular, matching η πόρτα and showing it’s the object of ανοίγεις inside the relative clause.

Could I use όπου instead of που?

No. όπου means “where” (locative). You’d use όπου with a place meaning: Η πόρτα όπου στέκεσαι = “the door where you are standing.” For “the door (that) you open,” use που or την οποία.

What difference would past or future tenses make?

Past action in the relative clause: Η πόρτα που άνοιξες δεν κλείνει καλά. = “The door that you opened doesn’t close well.”
Future in the main clause: Η πόρτα που ανοίγεις δεν θα κλείσει καλά. = “The door you are opening won’t close well.”

Is κλείνει transitive or intransitive here? How would I say “you don’t close it well”?

Here κλείνει is intransitive: “it (the door) doesn’t close well.” If you want “you don’t close it well,” make it transitive with a clitic object: Δεν την κλείνεις καλά. Different meaning: one blames the door; the other blames the person.

What are the gender and case for Η πόρτα? Why Η and not Το?

πόρτα is a feminine noun; Η is the feminine nominative singular article, used because η πόρτα is the subject of the main clause. As an object it would be την πόρτα (accusative). In the relative clause the object role is represented by που, not by repeating την πόρτα.

Any quick pronunciation tips?

Η πόρτα: [EE POR-ta] (tapped/flapped r)
που: [pu]
ανοίγεις: [a-NEE-yees] (the γ before ει sounds like a soft “y”)
δεν: [then] (like English “then”)
κλείνει: [KLEE-nee] (ει sounds like “ee”)
καλά: [ka-LA] (stress on the last syllable)

Stress marks in Greek show the stressed syllable: πόρτα, ανοίγεις, κλείνει, καλά.