Waar wacht jij op? Ik wacht op mijn instapkaart, want zonder die kom ik de veiligheidscontrole niet door.

Because wachten op is the normal Dutch combination for to wait for.

With waar + a preposition, Dutch has two common patterns:

• Waar wacht je op? — very common in everyday speech
• Waarop wacht je? — more formal or written

So Waar wacht jij op? is completely normal. English also often leaves the preposition at the end, so this pattern may feel familiar.

Both are possible:

• Waar wacht je op? — neutral, very common
• Waar wacht jij op? — a bit more emphatic

Using jij can add stress, as if the speaker means you in particular. It can also just sound slightly clearer or stronger in speech.

Because this is a direct question, and Dutch normally uses inversion in main-clause questions:

• statement: Jij wacht op mijn instapkaart.
• question: Waar wacht jij op?

So once something else comes first, the verb usually comes before the subject.

Yes. Wachten op is a fixed verb + preposition combination.

Examples:

• Ik wacht op de bus.
• We wachten op toestemming.

English says wait for, while Dutch says wachten op. So you should learn the verb together with its preposition.

Instapkaart means boarding pass.

It is a compound noun:

• instappen = to board, to get on
• kaart = card, ticket

Dutch forms compounds very often, and they are usually written as one word. So instapkaart is one noun, not two separate words.

Die here means that one and refers back to mijn instapkaart.

So:

• zonder die = without that one

This is very natural in Dutch. Instead of repeating the noun, Dutch often uses die or dat.

Because instapkaart is a de-word, the pronoun is die:

• de kaart → die
• het ticket → dat

So if the noun were het ticket, you would expect zonder dat.

Sometimes Dutch can use a personal pronoun for objects, but here die is more natural.

Compare:

• zonder die — without that one
• zonder hem — possible in some contexts, but less natural here

For objects that were just mentioned, Dutch often prefers a demonstrative pronoun like die or dat, especially when pointing back to a specific thing.

It means security check or security screening.

It is another Dutch compound:

• veiligheid = safety, security
• controle = check, inspection

Dutch very often joins nouns together into one word. The grammatical gender and article usually come from the last part of the compound. Since controle is a de-word, the full compound is also de veiligheidscontrole.

This means I can’t get through security.

A useful way to understand it is:

• door = through
• komen = come, get
• de veiligheidscontrole door komen = to get through the security check

In this kind of expression, door often appears near the end of the clause. So the word order may look unusual at first:

• Ik kom de veiligheidscontrole niet door.

A very similar idea in more straightforward order is:

• Ik kom niet door de veiligheidscontrole.

Both express getting through something.

Dutch often moves a phrase to the front for emphasis or to set the scene.

So:

• Zonder die kom ik de veiligheidscontrole niet door.

literally starts with Without that... and then the rest follows. Once a phrase is placed first, Dutch again uses inversion:

• first: zonder die
• then verb: kom
• then subject: ik

That is why it is zonder die kom ik..., not zonder die ik kom...

Here niet negates the idea of getting through. In Dutch, niet often comes before the final part of the verb phrase or before a final particle-like word such as door in this expression.

So:

• Ik kom de veiligheidscontrole niet door.

The niet belongs with the whole idea get through the security check.

This placement is normal and idiomatic.

Both can mean because, but they work differently.

• want introduces a new main clause
• omdat introduces a subordinate clause

So with want, you keep normal main-clause word order:

• Ik wacht op mijn instapkaart, want zonder die kom ik de veiligheidscontrole niet door.

With omdat, the word order changes:

• Ik wacht op mijn instapkaart, omdat ik zonder die niet door de veiligheidscontrole kom.

So want is not more correct here; it just creates a different sentence structure.