Το πλυντήριο είναι ήδη γεμάτο, οπότε αφήνω το πιάτο στον νεροχύτη.

Because Greek uses the definite article very often, sometimes more often than English does.

• το πλυντήριο = the dishwasher / the washing machine
• το πιάτο = the plate

In this sentence, both nouns are neuter singular, so they take το in the nominative/accusative singular.

A useful thing to remember is that Greek normally does not drop the as freely as English sometimes does. So where English might say I leave the plate in the sink, Greek naturally keeps the articles: το πιάτο, τον νεροχύτη.

Because γεμάτο is an adjective agreeing with το πλυντήριο, which is neuter singular.

Greek adjectives change form to match the noun in:

• gender
• number
• case

Here:

• το πλυντήριο = neuter singular
• so the adjective is γεμάτο = neuter singular

Compare:

• ο νεροχύτης είναι γεμάτος = the sink is full
• η τσάντα είναι γεμάτη = the bag is full
• το πλυντήριο είναι γεμάτο = the dishwasher is full

So the ending changes depending on what the adjective describes.

By itself, πλυντήριο can mean a washing machine in many contexts. More specifically:

• πλυντήριο ρούχων = washing machine
• πλυντήριο πιάτων = dishwasher

In everyday speech, Greek speakers may shorten this and just say πλυντήριο if the context makes it obvious. Since the sentence mentions a plate and the sink, the intended meaning here is clearly dishwasher.

So yes: the context is doing important work here.

ήδη means already.

So:

• είναι ήδη γεμάτο = is already full

Its position is very natural here: it comes before the adjective phrase γεμάτο. Greek adverbs like ήδη are fairly flexible, but this placement is common and straightforward.

You may also hear similar adverbs in similar positions:

• είναι ήδη έτοιμο = it is already ready
• έχω ήδη φάει = I have already eaten

Here, οπότε means so, therefore, or as a result.

It connects the two parts of the sentence:

• Το πλυντήριο είναι ήδη γεμάτο
• οπότε αφήνω το πιάτο στον νεροχύτη

So the second action happens as a consequence of the first.

A useful note: οπότε can also sometimes mean when or whenever in other contexts, so learners sometimes get confused. But in this sentence it clearly means so / therefore.

Example:

• Δεν έχω χρόνο, οπότε φεύγω τώρα.
  = I don’t have time, so I’m leaving now.

Αφήνω is the present tense, first person singular: I leave / I am leaving.

In Greek, the present tense can be used in ways that feel very natural in everyday speech, including:

• habitual action
• immediate action
• vivid, conversational present

So αφήνω το πιάτο στον νεροχύτη can sound like:

• I leave the plate in the sink
• So I’m leaving the plate in the sink

depending on context.

If you wanted a more explicit future meaning, you could say:

• θα αφήσω το πιάτο στον νεροχύτη = I’ll leave the plate in the sink

But the plain present here is perfectly natural.

Στον is a contraction of:

• σε + τον = στον

So:

• στον νεροχύτη = in/at the sink

Greek very often combines σε with the definite article:

• σε + το = στο
• σε + τον = στον
• σε + την = στην
• σε + τους = στους, etc.

Here νεροχύτης is a masculine noun, so the article is τον, and after contraction you get στον.

Because νεροχύτης is a masculine noun, and after σε it appears in the accusative case.

Dictionary form:

• ο νεροχύτης = nominative

After σε:

• στον νεροχύτη = accusative

This is a very common pattern for masculine nouns in -ης:

• ο μαθητής → τον μαθητή
• ο οδηγός → τον οδηγό
• ο νεροχύτης → τον νεροχύτη

So the ending changes because the noun is governed by σε.

It actually is in the accusative, but for many neuter nouns, the nominative and accusative forms look the same.

So:

• nominative: το πιάτο
• accusative: το πιάτο

Since αφήνω takes a direct object, το πιάτο is in the accusative case, but there is no visible change in the noun itself.

This is very common with neuter nouns:

• το βιβλίο → βλέπω το βιβλίο
• το παιδί → βλέπω το παιδί
• το πιάτο → αφήνω το πιάτο

In this sentence, it is best understood as in the sink.

The preposition σε has a broad range of meanings and can correspond to English:

• in
• on
• at
• to

So Greek often uses σε where English chooses a more specific preposition.

Examples:

• στο σπίτι = at home / in the house
• στο τραπέζι = on the table
• στον νεροχύτη = in the sink

So don’t expect a one-to-one match between σε and a single English preposition.

Greek word order is more flexible than English word order, though some versions sound more natural than others.

The given sentence is very natural:

• Το πλυντήριο είναι ήδη γεμάτο, οπότε αφήνω το πιάτο στον νεροχύτη.

But Greek can move things for emphasis. For example:

• Το πιάτο το αφήνω στον νεροχύτη...
  puts more focus on the plate
• Ήδη είναι γεμάτο το πλυντήριο...
  sounds marked or emphatic

The standard version you were given is neutral and good to learn first.

Yes, but the nuance changes a bit.

• βάζω = I put
• αφήνω = I leave

So:

• βάζω το πιάτο στον νεροχύτη focuses more on the act of placing it there
• αφήνω το πιάτο στον νεροχύτη emphasizes leaving it there because you’re not dealing with it now

In this sentence, αφήνω fits well because the dishwasher is full, so the speaker is leaving the plate in the sink for the time being.

νεροχύτη is pronounced roughly neh-roh-KHEE-tee, with the stress on χύ.

The letter χ is not like English ch in chair. It is a fricative sound. Before ι/η/ε/αι/ει/οι/υ, it is the softer sound you hear in words like German ich. English does not have an exact equivalent.

So:

• νεροχύτη → stress on the second-to-last syllable
• the χ is a soft, breathy consonant

If pronunciation is your focus, it may help to listen to native audio a few times and imitate the sound rather than trying to map it exactly onto English.

Because οπότε introduces the second clause, and Greek normally separates this kind of clause with a comma.

So the sentence has two linked parts:

1. Το πλυντήριο είναι ήδη γεμάτο
2. οπότε αφήνω το πιάτο στον νεροχύτη

This punctuation is standard and helps show the logical connection: X is true, so Y happens.

Greek punctuation in such sentences often resembles English, so this comma will feel familiar.