Aștept la ușă până vine curierul.

A word-by-word breakdown is:

• Aștept = I wait / I am waiting
• la = at
• ușă = door
• până = until
• vine = comes
• curierul = the courier

So the structure is literally:

• I wait at door until comes the courier

Natural English: I wait at the door until the courier comes.

Romanian usually drops subject pronouns when the verb already makes the subject clear.

• aștept = I wait
• aștepți = you wait
• așteaptă = he/she waits

Because aștept already shows I, you do not need eu.

You could say Eu aștept la ușă... if you want extra emphasis, like I’m the one waiting at the door.

-ul is the Romanian definite article attached to the end of the noun.

• curier = courier
• curierul = the courier

Romanian usually puts the at the end of the noun instead of using a separate word before it.

Other examples:

• băiat = boy
• băiatul = the boy

So vine curierul means the courier comes / is coming.

Romanian often uses the present tense after până when talking about a future event, just like English often does after until.

• Aștept până vine curierul. = I’ll wait until the courier comes.

Even though the action is in the future, vine stays in the present form.

This is very natural in Romanian.

Yes. la ușă means at the door.

The preposition la is commonly used for location in expressions like this:

• la masă = at the table
• la fereastră = at the window
• la ușă = at the door

It does not mean you are literally on the door. It means you are positioned by it.

Because after la, Romanian often uses the noun without the definite article when the meaning is general or idiomatic.

So:

• la ușă = at the door

In many everyday expressions, Romanian prefers this article-less form.

You can also hear definite forms in some contexts, but la ușă is the normal, natural expression here.

Not exactly by itself.

In Aștept la ușă până vine curierul, the main idea is:

• I’m waiting at the door until the courier comes.

If you want to say I’m waiting for the courier, Romanian normally says:

• Aștept curierul.

Notice something important: Romanian a aștepta usually takes a direct object without a word for for.

So:

• Aștept curierul = I’m waiting for the courier
• not literally something like aștept pentru curier

In your sentence, the courier is not the direct object of aștept. Instead, până vine curierul tells you until what moment you are waiting.

Yes, Romanian word order is somewhat flexible, but the original order is very natural:

• Aștept la ușă până vine curierul.

You could also say:

• Până vine curierul, aștept la ușă.

This puts more focus on until the courier comes.

Romanian allows this kind of reordering more easily than English, but the original version is the most straightforward for a learner.

A simple approximate pronunciation is:

UH-shtept la OO-shuh PUH-nuh VEE-neh koo-ree-E-rul

A few helpful sound notes:

• ă is a short neutral vowel, like the a in sofa
• ș sounds like sh
• ț sounds like ts

So:

• Aștept sounds roughly like uh-shtept
• ușă sounds roughly like oo-shuh
• până sounds roughly like puh-nuh

Yes.

The infinitive is:

• a veni = to come

Here are a few present-tense forms:

• eu vin = I come
• tu vii = you come
• el/ea vine = he/she comes

So in până vine curierul, vine means comes or is coming, depending on context.