قبل أن نبدأ الرحلة، أضع الخريطة في الحقيبة.

Before we start the trip, I put the map in the bag.

Breakdown of قبل أن نبدأ الرحلة، أضع الخريطة في الحقيبة.

• في: in
• أن: (subordinating particle)
• يبدأ: to start
• قبل: before

Questions & Answers about قبل أن نبدأ الرحلة، أضع الخريطة في الحقيبة.

Why does the sentence use قبل أن instead of just قبل?

Because قبل by itself usually comes before a noun, while قبل أن is used before a verb.

• قبل الرحلة = before the trip
• قبل أن نبدأ الرحلة = before we start the trip

So أن is what lets قبل introduce a whole verbal clause.

What is أن doing here grammatically?

Here أن is a particle that is followed by a present-tense verb and turns it into a subordinated clause.

In this sentence:

• أن نبدأ = that we begin / to begin / we begin in a dependent clause

After words like قبل and بعد, this structure is very common:

• قبل أن... = before ...
• بعد أن... = after ...

So قبل أن نبدأ الرحلة literally has the structure before [we begin the trip].

Why is the verb نبدأ used after أن, and does its form change?

Yes. After أن, the present-tense verb is normally in the subjunctive mood in MSA.

So the fully vowelled form would be:

• نبدأُ in the normal indicative