Együttműködünk, és együtt készítjük a vendéglistát.

A natural breakdown is:

• együttműködünk = we cooperate / we work together
• és = and
• együtt = together
• készítjük = we make / we prepare
• a = the
• vendéglistát = guest list (as a direct object)

So the sentence has two coordinated parts:

1. Együttműködünk
2. és együtt készítjük a vendéglistát

The second part literally looks like and together we prepare the guest list.

Because they are doing two different jobs.

• In együttműködünk, the element együtt is part of a single verb: együttműködik = to cooperate
• Later, együtt is an independent adverb meaning together

So:

• együttműködünk = one lexical verb, we cooperate
• együtt készítjük = we make it together

This is very common in Hungarian: something that originally looks like multiple parts may function as one established verb.

The ending -ünk marks:

• 1st person plural = we
• in the indefinite verb conjugation

So:

• együttműköd-ünk = we cooperate

Hungarian usually does not need the pronoun mi (we) unless you want emphasis, because the verb ending already tells you the subject.

So Mi együttműködünk is possible, but usually just Együttműködünk is enough.

Because Hungarian has two main conjugation patterns for many verbs:

• indefinite conjugation
• definite conjugation

Here, the verb has a specific direct object:

• a vendéglistát = the guest list

Since the object is definite, Hungarian uses the definite conjugation:

• készítjük = we make it / we prepare it

Compare:

• Készítünk egy vendéglistát. = We are making a guest list.
  → indefinite object
• Készítjük a vendéglistát. = We are making the guest list.
  → definite object

This is one of the biggest grammar points English speakers notice in Hungarian.

Because it is the direct object of the verb, so it takes the accusative ending.

• dictionary form: vendéglista = guest list
• accusative: vendéglistát = guest list as the thing being made/prepared

The accusative ending is usually -t, but the exact form can vary a little depending on sound patterns and linking vowels.

Here:

• vendéglista
  • -t → vendéglistát

The long á appears before the -t because of how this noun forms the accusative.

Yes. a is the definite article the before consonant-initial words.

Hungarian has two forms of the definite article:

• a before consonant sounds
• az before vowel sounds

So:

• a vendéglistát
• but az asztalt

In your sentence, a vendéglistát means the guest list, and that definiteness is also why the verb is készítjük.

Because Hungarian is a pro-drop language: the subject pronoun is often omitted when the verb ending already shows who the subject is.

Here the endings already tell us the subject is we:

• együttműködünk → we cooperate
• készítjük → we make/prepare it

So adding mi (we) is usually unnecessary unless you want contrast or emphasis:

• Mi együttműködünk, és együtt készítjük a vendéglistát.
  = We are cooperating and making the guest list together.
  (with extra emphasis on we)

Because the sentence is making two related but separate points:

1. Együttműködünk = We cooperate
2. együtt készítjük a vendéglistát = We make the guest list together

The second együtt is not redundant. It specifically tells you how they are making the guest list: jointly, together.

Without the second együtt, the sentence would still be grammatical:

• Együttműködünk, és készítjük a vendéglistát.

But that version does not stress the shared action as clearly.

Hungarian word order is fairly flexible, but changing it often changes the focus or emphasis.

Your sentence is neutral and natural:

• Együttműködünk, és együtt készítjük a vendéglistát.

Possible alternatives:

• A vendéglistát együtt készítjük.
  Emphasizes the guest list
• Együtt készítjük a vendéglistát.
  Neutral, but with nice emphasis on together
• Mi készítjük együtt a vendéglistát.
  Can sound contrastive, like we are the ones making it together

So yes, word order can change, but not always with exactly the same nuance.

Because Hungarian punctuation commonly uses a comma to separate coordinated clauses, especially when each clause has its own finite verb.

Here you have:

• Együttműködünk
• és együtt készítjük a vendéglistát

Since these are two full clauses, the comma is normal in Hungarian.

This is a place where Hungarian punctuation may feel a bit different from English habits.

It is in the present tense.

• együttműködünk = we cooperate / we are cooperating
• készítjük = we make / we are making it

Hungarian present tense can often correspond to either:

• simple present
• present progressive

depending on context.

So this sentence could mean something like:

• We cooperate, and we make the guest list together
• or We’re cooperating, and we’re putting the guest list together

The exact English choice depends on the situation.

A few parts may be especially hard for English speakers:

• gy in együtt is a soft consonant, somewhat like the dy sound in British duke for some speakers, but not exactly
• ű in működünk is a long front rounded vowel; English does not really have it
• ö and ü are also front rounded vowels
• ty in készítjük is another soft consonant, different from plain t

A rough learner-friendly approximation:

• együtt ≈ edy-üt
• működünk ≈ müü-kö-dünk
• készítjük ≈ kay-see-tyük
• vendéglistát ≈ ven-dayg-lee-staat

Also remember that Hungarian stress is usually on the first syllable of each word:

• Együttműködünk
• együtt
• készítjük
• vendéglistát

It can fit several English verbs depending on context.

készít is a broad verb meaning things like:

• make
• prepare
• produce
• draw up

So készítjük a vendéglistát could naturally be translated as:

• we’re making the guest list
• we’re preparing the guest list
• we’re drawing up the guest list

If the meaning has already been given to the learner, the key point is that készít is a very general and useful verb, often broader than any single English equivalent.

The two biggest grammar points here are:

1. Definite vs. indefinite verb conjugation
   • készítjük because the object is a vendéglistát
2. Accusative marking
   • vendéglistát because it is the direct object

So this sentence is a very good example of how Hungarian connects:

• the form of the noun
• and the form of the verb

That connection is something English does not do in the same way, so it is worth noticing early.