Hem de marxar aviat perquè el tren surt a les set.

Hem de means we have to or we must.

It comes from the structure haver de + infinitive, which is a very common way to express obligation in Catalan.

• hem = we have
• de = to
• marxar = leave

So Hem de marxar = We have to leave.

This is one of the most useful everyday patterns in Catalan:

• He de treballar = I have to work
• Has d’estudiar = You have to study
• Hem de marxar = We have to leave

Catalan often leaves out subject pronouns when they are not needed, just like Spanish or Italian.

So:

• Hem de marxar already clearly means we have to leave
• Nosaltres hem de marxar is possible, but it adds emphasis, as if you wanted to stress we

In normal conversation, the shorter version is more natural.

Marxar means to leave, to go away, or to depart.

It is not exactly the same as anar, which means to go in a more general sense.

Compare:

• Hem de marxar = We have to leave
• Hem d’anar a casa = We have to go home

So marxar focuses on leaving a place, while anar focuses more on going somewhere.

Sometimes yes, but they are not always identical.

• marxar = to leave, go away
• sortir = to go out, come out, leave from inside a place

In many everyday situations, both can work:

• Hem de marxar aviat
• Hem de sortir aviat

But marxar often sounds more like we need to go / we need to get going, while sortir can suggest physically going out from a place.

Aviat means soon or early, depending on context.

Here, Hem de marxar aviat means We have to leave soon / early.

Its position is very natural after the infinitive:

• Hem de marxar aviat

Catalan adverbs are often flexible in position, but this order is very common and natural.

Because perquè means because.

This is an important distinction in Catalan:

• perquè = because
• per què = why / for what
• per que = less common combination in other structures

So in this sentence:

• Hem de marxar aviat perquè el tren surt a les set = We have to leave early because the train leaves at seven

The accent helps distinguish because from other similar-looking forms.

Catalan often uses the present tense for scheduled future events, just like English does.

So:

• el tren surt a les set literally = the train leaves at seven

This is perfectly natural for timetables, plans, and schedules.

Compare in English:

• The train leaves at seven not necessarily
• The train will leave at seven

Catalan works the same way here.

Surt is the he/she/it form of sortir, meaning to go out, to come out, or to leave/depart.

In the context of transport:

• El tren surt a les set = The train leaves at seven / The train departs at seven

So although sortir often literally means to go out, it is also the normal verb for a train, bus, or plane departing.

Catalan uses the preposition a before clock times.

So:

• a les set = at seven
• a la una = at one

The article is used too:

• la una because it is singular
• les set because it is plural

This comes from the idea of understood hours:

• a les set (hores) = at seven (o’clock)

Because when telling time, Catalan uses the feminine article as if saying the seven hours.

That is why you get:

• la una
• les dues
• les tres
• les set

So les is not random; it is part of the standard way Catalan expresses clock time.

Yes, it is completely normal and natural.

The structure is:

• Hem de marxar aviat = main clause
• perquè el tren surt a les set = reason clause

This is very similar to English:

• We have to leave early because the train leaves at seven

Catalan word order is often quite close to English in sentences like this.

Usually, no.

In a sentence like this, Catalan normally does not use a comma before perquè when it simply introduces the reason:

• Hem de marxar aviat perquè el tren surt a les set.

That is the standard punctuation.

You could add emphasis in a few ways.

For example:

• Nosaltres hem de marxar aviat perquè el tren surt a les set.
  • stresses we
• Hem de marxar ben aviat perquè el tren surt a les set.
  • ben aviat = quite soon / very soon
• Hem de marxar aviat, perquè el tren surt a les set!
  • stronger intonation in speech

But the original sentence is already the most neutral and natural version.

A simple approximate pronunciation is:

Em de mar-SHAR uh-vee-AT per-KE el tren SOORT ah les SET

A few notes:

• h in hem is silent
• x in marxar sounds like sh
• què in perquè has stress on the last part: per-KE
• surt has a short vowel and a rolled or tapped r, depending on accent

Exact pronunciation varies somewhat across Catalan-speaking regions, but this approximation is a good start.