Learn Hardcore Hungarian: A másik bőrönd majdnem üres, abban csak egy könyv és egy térkép van. - The other suitcase is almost empty; in it there is only a book and a map.

With a definite article (a / az), it usually means the other (one):
- A másik bőrönd = the other suitcase (a specific one, known from context).
With an indefinite article (egy) or without an article, it can often mean another:
- Egy másik bőrönd = another suitcase (not a specific one).
- Másik bőrönd is van = There is another suitcase too.

In your sentence, A másik bőrönd clearly means the other suitcase.

Why is there no van in A másik bőrönd majdnem üres? Would A másik bőrönd majdnem üres van work?

Hungarian normally omits the present-tense form of van in sentences where:

the predicate is an adjective or a noun, and
the sentence is in the third person present.

So you say:

A bőrönd üres. = The suitcase is empty. (not A bőrönd üres van.)
A könyv régi. = The book is old. (not régi van)

In your sentence:

A másik bőrönd majdnem üres. = The other suitcase is almost empty.

Adding van (A másik bőrönd majdnem üres van) is wrong in standard Hungarian.

What does majdnem mean, and where does it usually go in the sentence?

Majdnem means almost / nearly.

It typically comes right before the word it modifies:

majdnem üres = almost empty
majdnem kész = almost ready
majdnem elestem = I almost fell

In your sentence:

majdnem modifies üres, so majdnem üres = almost empty.

You can change the word order for emphasis, e.g.:

Majdnem üres a másik bőrönd. – Almost empty is the other suitcase.
But the neutral, most common version is exactly what you have:
A másik bőrönd majdnem üres.

What is abban made of, and why not repeat a bőröndben instead?

Abban is a combination of:

az (that) + -ban/-ben (the inessive case, “in”)
→ azban → assimilation: abban

So abban literally means in that (one).

In context:

A másik bőrönd majdnem üres, abban csak egy könyv és egy térkép van.
= The other suitcase is almost empty; in that (suitcase) there is only a book and a map.

Instead of repeating:

✗ … a másik bőröndben csak egy könyv és egy térkép van. Hungarian often prefers a pronoun:
abban = in that (suitcase).

You could say abban a bőröndben (“in that suitcase”), but it sounds heavier and is not necessary since the suitcase is already clear from context.

What is the difference between abban and benne?

Both refer to something being inside something else, but:

abban = in that (one)
- form: demonstrative (az) + case ending (-ban/-ben)
- used when you’re clearly pointing to something specific mentioned before:
  - A másik bőrönd majdnem üres, abban… = in that (suitcase)…
benne = in it / inside it (more like a general “in it”)
- form: stem ben-
  - 3rd person suffix -ne
- less demonstrative, more like a simple pronoun.

For your exact sentence, abban is better because it strongly connects back to A másik bőrönd (“that suitcase”).

What does csak mean here, and why is it before egy könyv?

Csak means only / just.

Its position shows what is being limited. In your sentence:

Abban csak egy könyv és egy térkép van.
= In that (suitcase) there is only a book and a map.
(Nothing else is in there.)

If you move csak, you change the emphasis slightly:

Csak abban van egy könyv és egy térkép.
= Only in that one is there a book and a map.
(No other suitcase has them.)

So in your original sentence, csak directly limits egy könyv és egy térkép, meaning those are the only contents.

Does egy here mean a or one? Is it counting or just the article?

Egy can mean either:

the indefinite article a / an, or
the numeral one.

In egy könyv és egy térkép, it can be understood both as:

a book and a map, or
one book and one map.

Usually, in neutral sentences like this, learners can safely read it as a book and a map.
If the speaker wants to stress exactly one, they normally rely on context or extra emphasis in speech, not on a different word.

Why is van used in the second clause but not in the first?

Two different types of sentences are involved:

Predicate with adjective (state):
- A másik bőrönd majdnem üres.
  → verb van is omitted in 3rd person present.
  (As explained earlier: A bőrönd üres not üres van.)
Existential / locative sentence (there is / are somewhere):
- Abban csak egy könyv és egy térkép van.
  = Literally: In that, only a book and a map are.
  In this type, van / vannak is kept in the present tense.

So:

State / quality → drop van (in 3rd person present).
Existence / location → keep van/vannak.

Why is it egy könyv és egy térkép van (singular van) and not vannak?

In Hungarian, when you have an existential / “there is” sentence with a list of things, it is very common (and fully correct) to use the singular verb:

Az asztalon egy könyv és egy toll van.
= On the table there is a book and a pen.

So your sentence:

Abban csak egy könyv és egy térkép van.
is perfectly natural.

Vannak is not impossible, but it sounds heavier and less neutral in this listing context. The singular van is the normal choice here.

Can I change the word order of the second clause? For example: Csak egy könyv és egy térkép van abban?

Yes, Hungarian allows flexible word order to change focus and emphasis.

Your version:

Abban csak egy könyv és egy térkép van.
→ neutral: talking about what is in that suitcase.

Alternative:

Csak egy könyv és egy térkép van abban.
→ slightly more emphasis on only a book and a map; the place (abban) is less central.

Both are grammatically correct. The original sounds like a straightforward description of the suitcase’s contents; your alternative might be used if the contrast is more about how little is in there.