اول ما القطر يوصل المحطة، هانزل.

Here أول ما is a fixed expression meaning as soon as, once, or the moment that.

So in this sentence:

• أول ما القطر يوصل المحطة = as soon as the train arrives at the station

The ما here does not mean what in the normal question-word sense. In this pattern, it is just part of the time expression أول ما.

That is a very common question in Egyptian Arabic.

After time expressions like أول ما, Egyptian often uses the bare imperfect form, so:

• يوصل = arrive / arrives / will arrive, depending on context

In this sentence, it refers to a future event because the whole meaning is future:

• As soon as the train arrives, I’ll get off.

Why not the other forms?

• بيوصل usually suggests a present or habitual meaning, like it arrives / it usually arrives
• هيوصل is a clear future form, it will arrive

After أول ما, the bare form يوصل is very natural and common.

هانزل means I will get off or I will get down.

It comes from the verb نزل.

In Egyptian Arabic:

• بنزل = I get off / I get down / I am getting off
• هانزل = I will get off / I’ll get down

The prefix هـ or ها marks the future in Egyptian Arabic.

So:

• هانزل = ha-
  • the verb form = I will get off

Because the verb itself already shows the subject.

In هانزل, the verb form tells you it is first person singular, so I is already built into the verb.

That means:

• هانزل = I will get off

You can say أنا هانزل, but that usually adds emphasis, such as:

• I’m the one who will get off
• As for me, I’ll get off

Without أنا, the sentence is still completely normal and complete.

Yes, literally نزل is connected with the idea of going down or descending.

But in Arabic, it is also the normal verb used for getting off a bus, train, taxi, etc.

So in transportation contexts:

• أنزل من القطر = I get off the train
• هانزل in this sentence = I’ll get off

This is one of those places where Arabic and English use slightly different literal images:

• English says get off
• Arabic says something closer to go down

But the practical meaning is the same.

In Egyptian Arabic, القطر is a common colloquial word for the train.

By contrast:

• القطار is the standard/formal form you would expect in Modern Standard Arabic
• القطر is a natural Egyptian colloquial form

So this sentence is very much in spoken Egyptian style.

A learner who knows MSA might expect القطار, but القطر is normal in Egyptian speech.

المحطة means the station.

In this sentence, the station is understood as a specific, known one — usually the station the speaker is waiting for or planning to get off at.

So:

• القطر يوصل المحطة = the train arrives at the station

Using the definite article sounds natural because the speaker has a particular station in mind.

Also, in context, since we are already talking about a train journey, the station is easy to understand without saying more.

In Egyptian Arabic, subject + verb order is very common, especially in everyday speech.

So:

• القطر يوصل = the train arrives

This sounds natural in colloquial Egyptian.

You may also see verb + subject order in other kinds of Arabic, especially in more formal or literary styles, but in spoken Egyptian, putting the subject first is extremely common.

So this sentence sounds conversational and natural.

Yes. You could also say:

• هانزل أول ما القطر يوصل المحطة

That still means the same thing: I’ll get off as soon as the train arrives at the station.

The version with أول ما... first puts the time condition up front:

• As soon as the train arrives at the station, I’ll get off.

That structure is very natural because it sets the scene first and then gives the main action.

The comma simply marks a pause in writing; it is not changing the grammar in any major way.

It is specifically Egyptian Arabic in both wording and style.

A more formal Modern Standard Arabic version would normally look different, for example:

• بمجرد أن يصل القطار إلى المحطة، سأنزل.

Some main differences are:

• Egyptian uses القطر instead of MSA القطار
• Egyptian uses المحطة directly after the verb, while MSA often uses إلى المحطة
• Egyptian uses هانزل for the future, while MSA would use سأنزل

So if you learned MSA first, this sentence may feel familiar in meaning but noticeably different in form.