Die Fluggesellschaft informiert uns über die Verspätung, bevor wir abfliegen.

German very often forms compound nouns by joining smaller words together.

• Flug = flight
• Gesellschaft = company / corporation / association

So Fluggesellschaft is literally flight company, which is the normal German word for airline.

This is completely normal in German. English often uses separate words where German uses one combined noun.

Because Fluggesellschaft is a feminine noun in German.

That means its basic article is die:

• die Fluggesellschaft = the airline

In this sentence, it is also the subject of the sentence, so it is in the nominative case. For a feminine singular noun, the nominative article is still die.

Because uns is the object form of wir.

• wir = we
• uns = us

Here, the airline is doing the action of informing, and us is receiving that action. So German uses the accusative object pronoun:

• Die Fluggesellschaft informiert uns = The airline informs us

If you used wir, it would incorrectly make we the subject.

The verb informieren often follows this pattern:

• jemanden über etwas informieren = to inform someone about something

So in this sentence:

• uns = someone being informed
• über die Verspätung = about the delay

This is a very useful structure to remember as a chunk:

• jemanden über etwas informieren

Here über means about/regarding, not over in a physical sense.

With this meaning, über takes the accusative case.

So:

• über die Verspätung = about the delay

Also, Verspätung is a feminine noun, and the feminine singular article in the accusative is also die. So even though it is accusative, it still looks like:

• die Verspätung

Verspätung means delay.

It comes from the adjective spät = late, and the noun refers to lateness or a delay in travel, schedules, arrivals, departures, and so on.

You will see it a lot in transport contexts:

• Die Verspätung = the delay
• wegen der Verspätung = because of the delay

Because bevor introduces a subordinate clause, and in German, subordinate clauses are normally separated from the main clause by a comma.

So:

• Die Fluggesellschaft informiert uns über die Verspätung, bevor wir abfliegen.

That comma is required in standard German spelling.

Because bevor is a subordinating conjunction meaning before.

After a subordinating conjunction in German, the conjugated verb goes to the end of the clause.

So:

• bevor wir abfliegen

not

• bevor wir fliegen ab
• bevor abfliegen wir

This verb-final word order is one of the most important patterns in German subordinate clauses.

Good question. abfliegen is a separable verb.

In a normal main clause, it often splits:

• Wir fliegen ab. = We depart.

But in a subordinate clause, the verb usually goes to the end as one whole unit, so the prefix does not split off:

• bevor wir abfliegen

So the rule is:

• main clause: separable verb often splits
• subordinate clause: separable verb usually stays together at the end

Because German often uses the present tense to talk about the future when the context already makes the time clear.

Here, bevor wir abfliegen clearly refers to a future event, so German does not need a special future form.

This is very common:

• Morgen fliegen wir ab. = We leave tomorrow.
• Bevor wir abfliegen... = Before we depart...

German does have a future tense, but it is often unnecessary in everyday speech.

Not in this sentence.

Use bevor before a clause with a subject and verb:

• bevor wir abfliegen

Use vor before a noun phrase:

• vor dem Abflug = before the departure

So these are both correct, but they are structured differently:

• bevor wir abfliegen
• vor dem Abflug

But vor wir abfliegen is not standard German.

Yes. You can say:

• Bevor wir abfliegen, informiert uns die Fluggesellschaft über die Verspätung.

That is also correct.

When the subordinate clause comes first, the main clause still follows the verb-second rule, so the conjugated verb comes immediately after the first element:

• Bevor wir abfliegen, informiert ...
• not Bevor wir abfliegen, die Fluggesellschaft informiert ...

So moving the clause changes the word order, but not the core meaning.