Learn Hardcore Greek: Αφήνω τα κλειδιά μου πάνω στο τραπέζι στο σαλόνι. - I leave my keys on the table in the living room.

Αφήνω already means I leave (1st person singular).
Adding εγώ is only needed for emphasis or contrast:
- Εγώ αφήνω τα κλειδιά μου… = I leave my keys… (as opposed to someone else).

So:

Αφήνω τα κλειδιά μου… = natural, neutral.
Εγώ αφήνω τα κλειδιά μου… = “I (and not someone else) leave my keys…”

What tense is αφήνω, and does it mean “I leave” or “I am leaving”? Is there a difference in Greek?

Αφήνω is the present tense, 1st person singular, of the verb αφήνω (to leave / to let / to allow).

Greek present tense usually covers both:

English simple present: I leave my keys on the table.
English present continuous: I am leaving my keys on the table.

So Αφήνω τα κλειδιά μου… can mean:

a habitual action: “I (usually) leave my keys…”
an action happening right now: “I am leaving my keys…”

Context decides which English translation is best, but Greek uses the same form αφήνω for both.

Why is it τα κλειδιά and not something like οι κλειδιά? How does the article work here?

In Greek, the definite article must agree with the noun in:

Gender
Number
Case

The noun κλειδί (key) is:

Neuter, singular: το κλειδί
Plural: τα κλειδιά

In the sentence:

We have plural (keys, not one key).
The keys are a direct object, so they are in the accusative case.
Neuter plural accusative article is τα.

So:

τα κλειδιά = the keys (neuter, plural, accusative)

There is no οι κλειδιά because οι is for masculine plural, not neuter.

What is the form κλειδιά? How is it related to κλειδί?

Κλειδί is the singular: το κλειδί = the key.

The plural is:

τα κλειδιά = the keys.

So the pattern is:

Singular: το κλειδί
Plural: τα κλειδιά

This is a common type of neuter noun whose plural ends in -ιά.

Why is the possessive μου after the noun (τα κλειδιά μου) and not before it, like in English?

In Greek, short possessive forms like μου, σου, του, της, μας, σας, τους usually follow the noun:

το βιβλίο μου = my book
τα κλειδιά μου = my keys

So the normal order is:

[article] + [noun] + [possessive clitic]

Putting the possessive before the noun (μου τα κλειδιά) sounds wrong or at best extremely marked in modern Greek.
In everyday Greek, you always say τα κλειδιά μου, το αυτοκίνητό του, etc.

Is μου here stressed or unstressed? Can I say τα δικά μου κλειδιά instead of τα κλειδιά μου?

In τα κλειδιά μου, the μου is an unstressed clitic possessive pronoun. It’s the normal, neutral way to say my keys.

You can also say:

τα δικά μου κλειδιά = my own keys / the keys that belong to me (as opposed to someone else)

This form:

Uses δικός/δική/δικό (own; emphatic possessive).
Adds an element of emphasis or contrast.

So:

τα κλειδιά μου = my keys (neutral).
τα δικά μου κλειδιά = my keys (not someone else’s) / emphasizes whose keys they are.

What case is τα κλειδιά μου in, and why?

Τα κλειδιά μου is in the accusative case.

Reasons:

It is the direct object of the verb αφήνω (I leave what? → the keys).
Direct objects in Greek take the accusative.

So:

Αφήνω τι; → τα κλειδιά μου → accusative.

What exactly does πάνω mean here, and could we leave it out and just say Αφήνω τα κλειδιά μου στο τραπέζι?

Πάνω literally means on (top) or above.

πάνω στο τραπέζι = on (top of) the table.

If you say only:

στο τραπέζι = at the table / on the table (often still understood as on top, but a bit more general/less explicit).

Both are possible:

Αφήνω τα κλειδιά μου στο τραπέζι.
Αφήνω τα κλειδιά μου πάνω στο τραπέζι.

Adding πάνω:

Makes it very clear that the keys are on top of the table’s surface.
Sounds very natural in everyday speech for physical placement.

What is στο? Is it one word or two words combined?

Στο is a contraction of two words:

σε (a general preposition: in, at, on, to)
το (neuter, singular, accusative article: the)

So:

σε + το = στο

In the sentence, we have:

στο τραπέζι = at/on the table
στο σαλόνι = in the living room

Both τραπέζι and σαλόνι are neuter singular nouns in the accusative, governed by the preposition σε.

Why is τραπέζι in the accusative after στο? I thought locations might take another case.

In modern Greek, after the preposition σε, nouns almost always take the accusative case, even for locations.

So:

σε + το τραπέζι → στο τραπέζι (accusative)
σε + το σαλόνι → στο σαλόνι (accusative)

Unlike some languages that use different cases for motion vs location, modern Greek generally:

Uses σε + accusative for both in/at/on (location) and into/onto (movement), with the verb and context clarifying the meaning.

Here, αφήνω shows we’re talking about location: the keys end up on the table, in the living room.

Why are there two στο phrases: πάνω στο τραπέζι and στο σαλόνι? How do they work together?

The two phrases give more detailed location, from specific to more general:

πάνω στο τραπέζι = on the table
(στο) σαλόνι = in the living room

Together:

πάνω στο τραπέζι στο σαλόνι = on the table that is in the living room.

It’s like saying in English:

I leave my keys on the table in the living room.

Greek allows you to chain these location phrases:

πάνω στο τραπέζι (more specific surface)
στο σαλόνι (room where that table is)

Does στο σαλόνι mean “in the living room” or “to the living room”?

στο σαλόνι can mean either in the living room or to the living room, depending on the verb.

With a verb expressing location/state, it usually means in:
- Είμαι στο σαλόνι. = I am in the living room.
- Αφήνω τα κλειδιά μου στο σαλόνι. = I leave my keys in the living room.
With a verb of motion, it often means to:
- Πάω στο σαλόνι. = I go to the living room.

In your sentence, αφήνω (I leave) plus context of placing something gives the meaning in the living room.

Could the order be Αφήνω τα κλειδιά μου στο σαλόνι πάνω στο τραπέζι instead? Is that still correct?

Yes, that order is also grammatically correct and natural:

Αφήνω τα κλειδιά μου στο σαλόνι, πάνω στο τραπέζι.

Both:

πάνω στο τραπέζι στο σαλόνι
στο σαλόνι πάνω στο τραπέζι

are possible. The difference is mostly about focus/order of information:

πάνω στο τραπέζι στο σαλόνι: first specify the surface (table), then the room.
στο σαλόνι πάνω στο τραπέζι: first give the room (living room), then where in that room (on the table).

In everyday speech, both word orders occur; intonation often does the rest.

What is the difference between αφήνω and βάζω here? Could I say Βάζω τα κλειδιά μου πάνω στο τραπέζι στο σαλόνι?

You can say:

Βάζω τα κλειδιά μου πάνω στο τραπέζι στο σαλόνι.

But there is a nuance:

αφήνω = leave (often with the idea of leaving something behind or not taking it with you).
- Αφήνω τα κλειδιά μου… can suggest a habit or a deliberate choice where they remain.
βάζω = put/place (the physical action of placing something somewhere).
- Βάζω τα κλειδιά μου… focuses more on the act of putting them down, not so much on the fact they stay there.

So:

To describe a habitual spot or “this is where I leave them”: αφήνω is very natural.
To describe the action right now of putting them there: βάζω is also fine, but a bit different in nuance.

Is σαλόνι masculine, feminine, or neuter, and how do I know from the article?

Σαλόνι is a neuter noun.

You can tell from:

Its typical neuter ending -ι (in many cases).
The article it takes:
- Singular nominative/accusative: το σαλόνι
- With σε + το → στο σαλόνι

In your sentence:

στο σαλόνι = σε + το σαλόνι → confirms that σαλόνι is neuter singular.

Could the sentence start with the place phrase, like Στο σαλόνι αφήνω τα κλειδιά μου πάνω στο τραπέζι?

Yes, that is also correct and natural:

Στο σαλόνι αφήνω τα κλειδιά μου πάνω στο τραπέζι.

Greek word order is fairly flexible. Placing στο σαλόνι at the beginning:

Puts more emphasis on the location (in the living room).
Is similar to English: In the living room, I leave my keys on the table.

The core grammar (articles, cases, verb form) stays the same; you only change the order for emphasis or style.