Mire visszajössz, a szemét már ki lesz dobva, és a kuka üres lesz.

Here mire means by the time.

So:

• Mire visszajössz = By the time you come back

This is different from amikor, which usually just means when in a more neutral time sense.

Compare:

• Amikor visszajössz... = When you come back...
• Mire visszajössz... = By the time you come back...

Mire often suggests that something else will already be finished before that moment.

Hungarian very often uses the present tense to talk about the future when the time reference is clear from context.

So visszajössz literally looks like you come back, but in context it means you will come back.

That is completely normal in Hungarian, especially in time clauses:

• Ha holnap jössz... = If you come tomorrow...
• Amikor megérkezel... = When you arrive...
• Mire visszajössz... = By the time you come back...

The future meaning is understood from mire and from the situation.

It breaks down like this:

• vissza = back
• jössz = you come

Together:

• visszajössz = you come back / you return

This is a very common Hungarian pattern: a verbal prefix plus a basic verb.

Other examples:

• bemegy = goes in
• kijön = comes out
• visszamegy = goes back

So visszajön is the dictionary form, and visszajössz is the you form.

This is a Hungarian way to express something like an English future passive/resultative:

• ki = out
• lesz = will be
• dobva = thrown

So:

• ki lesz dobva = will be thrown out
• more naturally in English here: will have been taken out

This structure is:

• verbal prefix
• lesz
• -va/-ve form of the verb

It often describes the resulting state of an action, not just the action itself.

So a szemét már ki lesz dobva emphasizes that by that time, the trash will already be in the state of having been taken out.

Not exactly in the same way as English.

Hungarian does not use a passive voice nearly as much as English does. Instead, it often uses constructions like:

• ki van dobva = is thrown out / has been thrown out
• ki lesz dobva = will be thrown out

This is often described as a passive-like or resultative structure.

In everyday usage, it works very much like an English passive, but grammatically Hungarian handles it differently.

An active version would also be possible:

• Mire visszajössz, már kidobják a szemetet.

But that version focuses more on someone will throw it out, while ki lesz dobva focuses more on the completed result.

Because in Hungarian, verbal prefixes often separate when another element comes between them and the main verbal idea.

The basic idea is:

• kidob = throw out

But in this structure, the future auxiliary lesz and the participle dobva split the normal unit apart:

• ki lesz dobva

This is normal.

You can think of ki as still belonging to dobva, even though it stands earlier in the sentence.

Hungarian prefixes are very mobile, especially in more complex verb forms.

Because a szemét is the subject of the clause:

• a szemét már ki lesz dobva

Literally: the trash will already be thrown out

Since it is the subject, it appears in the basic nominative form:

• a szemét

If it were the direct object of an active verb, then you would see:

• kidobják a szemetet = they will throw out the trash

So:

• a szemét = subject form
• a szemetet = object form

Yes, szemét has more than one use.

Common meanings include:

• trash / garbage / rubbish
• jerk / mean person / scumbag in informal speech

In this sentence, the meaning is clearly trash/garbage because of the context:

• ki lesz dobva = will be thrown out
• a kuka üres lesz = the bin will be empty

So there is no ambiguity here.

Kuka means bin, trash can, or garbage container, depending on context.

In this sentence:

• a kuka üres lesz = the bin will be empty

It usually refers to the container where household trash goes.

A learner should know that kuka is a very everyday, common word.

Because Hungarian often prefers the simpler, more natural description of the resulting state.

So instead of saying:

• the bin will be emptied

the sentence says:

• the bin will be empty

That sounds very natural.

Compare:

• a kuka üres lesz = the bin will be empty
• a kuka ki lesz ürítve = the bin will have been emptied

Both can make sense, but the first is simpler and more idiomatic in many everyday situations.

Már means already.

So:

• a szemét már ki lesz dobva = the trash will already be taken out

It emphasizes that the action will be completed before the person returns.

This fits very well with mire:

• Mire visszajössz... = By the time you come back...
• már = already

Together they strongly suggest completedness before that future point.

Hungarian has more than one way to express future meaning.

One common way is:

• fog + infinitive

For example:

• vissza fogsz jönni = you will come back

But Hungarian also often uses:

1. present tense with future meaning
2. lesz to express a future state

In this sentence:

• visszajössz = present form with future meaning
• üres lesz = future state
• ki lesz dobva = future result/passive-like form

So no fog is needed.

Using fog everywhere would often sound heavier or less natural.

Because the sentence contains two separate future predicates:

1. a szemét már ki lesz dobva
2. a kuka üres lesz

Each clause needs its own predicate.

So the first says:

• will be thrown out

and the second says:

• will be empty

Hungarian does not usually omit the second lesz here.

The word order is natural and helps organize information.

A rough breakdown:

• a szemét = the topic/subject
• már = already
• ki lesz dobva = will be thrown out

So the sentence presents the trash as the thing being talked about, then adds that it will already be taken out.

Hungarian word order is flexible, but not random. It often reflects:

• topic
• focus
• what is new information
• what is emphasized

This order is neutral and natural in context.

Because the sentence refers to specific, identifiable things:

• the trash
• the bin

In a household context, both speaker and listener know which trash and which bin are meant.

So Hungarian uses:

• a szemét
• a kuka

This is very similar to English the in this kind of situation.

Yes, very often that is the best English translation.

Hungarian does not have a direct one-to-one tense equivalent of the English future perfect, but sentences like this often express the same idea.

So:

• Mire visszajössz, a szemét már ki lesz dobva...

can naturally become:

• By the time you come back, the trash will already have been taken out...

That is often better English than the more literal:

• By the time you come back, the trash will already be thrown out...

So the Hungarian structure is not literally an English future perfect tense, but it often corresponds to one in translation.

It is basically neutral everyday Hungarian.

Nothing in it is especially formal. It sounds like a normal thing someone might say at home.

A few notes:

• kuka is an everyday word
• ki lesz dobva is common and natural in speech
• the whole sentence sounds practical and conversational

So a learner can safely treat it as normal standard usage.