Tenemos que llegar temprano a la estación porque la salida del tren es a las ocho.

In Spanish, subject pronouns are often omitted because the verb ending already shows who is doing the action.

• Tenemos = we have
• So (Nosotros) tenemos que... and Tenemos que... mean the same thing.

Spanish usually leaves out nosotros unless the speaker wants extra emphasis, contrast, or clarity.

Tener que + infinitive is a very common structure meaning to have to do something.

So:

• tenemos que llegar = we have to arrive

Even though tener by itself means to have, in tener que it expresses obligation or necessity.

Examples:

• Tengo que estudiar = I have to study
• Tienen que salir = They have to leave

After tener que, Spanish uses an infinitive.

Structure:

• tener que + infinitive

So:

• tenemos que llegar
• not tenemos que llegamos

This is like English:

• we have to arrive not
• we have to we arrive

Other examples:

• Tengo que comer = I have to eat
• Tenemos que salir = We have to leave

Here temprano is being used as an adverb, not an adjective.

It describes how or when we have to arrive:

• llegar temprano = to arrive early

As an adverb, it does not change for gender or number.

Compare:

• un tren temprano = an early train
  Here temprano is an adjective describing tren
• llegar temprano = to arrive early
  Here temprano is an adverb describing llegar

Because llegar a means to arrive at / to arrive in.

So:

• llegar a la estación = arrive at the station

If you said en la estación, that would describe location, not destination:

• Estamos en la estación = We are at the station

A useful pattern:

• ir a = to go to
• llegar a = to arrive at

Porque and por qué are different:

• porque = because
• por qué = why

In this sentence, the second part gives the reason:

• porque la salida del tren es a las ocho = because the train’s departure is at eight

Compare:

• ¿Por qué llegamos temprano? = Why are we arriving early?
• Porque la salida del tren es a las ocho. = Because the train’s departure is at eight.

Yes. Salida can mean both exit and departure, depending on context.

In this sentence:

• la salida del tren = the departure of the train / the train’s departure

In other contexts:

• la salida on a sign often means exit

So the meaning depends on what comes next:

• la salida del tren = the train’s departure
• la salida de emergencia = emergency exit

Because de + el contracts to del.

So:

• de + el = del

That is why Spanish says:

• la salida del tren

This contraction is mandatory.

Compare:

• el libro del profesor = the teacher’s book
• la puerta del coche = the car door

The only common exception is when el is part of a proper name:

• de El Escorial
  not del Escorial

Spanish uses a to give clock time:

• a las ocho = at eight
• a las dos = at two

You use:

• a la una = at one
• a las
  • plural hour for all other times

Why las? Because the expression comes from las ocho horas, with horas understood but usually omitted.

So:

• Es a las ocho = It is at eight
• Es a la una = It is at one

It is understandable and grammatically fine, but in everyday speech many speakers would more naturally say:

• El tren sale a las ocho. = The train leaves at eight.

That version is simpler and very common.

Still, la salida del tren es a las ocho is perfectly possible, especially in more formal, informational, or schedule-based language.

Because the noun is la estación. Like all Spanish nouns, it has grammatical gender, and this one is feminine.

So you get:

• la estación
• una estación
• esta estación

Many nouns ending in -ción are feminine:

• la estación
• la información
• la situación
• la canción

This is a very useful pattern to remember.

Estación has an accent mark because of Spanish stress rules.

Without going too deeply into pronunciation rules, the accent shows that the stress falls on the last syllable:

• es-ta-ción

Many words ending in -ción have the written accent:

• estación
• información
• nación
• situación

That accent helps both pronunciation and spelling.

The sentence is natural as it stands, but Spanish word order is somewhat flexible.

For example, you could also say:

• Porque la salida del tren es a las ocho, tenemos que llegar temprano a la estación.

This puts the reason first:

• Because the train’s departure is at eight, we have to arrive early at the station.

You could also hear slight variations such as:

• Tenemos que llegar a la estación temprano...

Both are fine. The original version is very natural and clear.