Avui vaig a la ciutat en tren, i la meva germana m'espera a l'andana.

Great question. In Catalan, vaig can appear in two different structures:

• vaig on its own = I go / I am going
  
  • from the verb anar = to go
• vaig + infinitive = a past tense, often equivalent to I did / I went / I ...-ed
  
  • for example: vaig anar = I went

So in Avui vaig a la ciutat, the verb is just vaig, with no infinitive after it, so it means I go or I’m going.

The preposition a means to when talking about movement toward a place.

• vaig a la ciutat = I go to the city
• vaig a casa = I go home
• vaig a l’escola = I go to school

So a la ciutat is simply to the city.

Catalan often uses the definite article more regularly than English does.

• la ciutat = the city

In this sentence, a la ciutat literally means to the city.
Using the article is completely normal here.

English sometimes drops articles where Catalan keeps them, so this is something learners often need to get used to.

In Catalan, en is commonly used to express means of transport.

• en tren = by train
• en cotxe = by car
• en autobús = by bus
• en avió = by plane

So Avui vaig a la ciutat en tren means Today I’m going to the city by train.

Catalan normally uses the definite article with possessives.

• la meva germana = literally the my sister, but naturally translated as my sister
• el meu pare = my father
• la nostra casa = our house

This is one of the big differences from English. In standard Catalan, la meva germana is the usual form.

m’espera is made of two parts:

• m’ = me
• espera = waits / is waiting

So m’espera means waits for me or is waiting for me.

The full part:

• la meva germana m’espera = my sister is waiting for me

Catalan often uses object pronouns before the verb, unlike English.

The full pronoun is em = me, but before a vowel or silent h, it is usually shortened to m’.

• em veu = he/she sees me
• m’espera = he/she waits for me
• m’ajuda = he/she helps me

Because espera begins with a vowel sound, em espera becomes m’espera.

This is because of elision. When the article la comes before a word beginning with a vowel, it often drops the a and becomes l’.

• la andana → l’andana
• la escola → l’escola
• la amiga → l’amiga

So:

• a l’andana = at the platform

This is very common in Catalan spelling.

In this sentence, andana means platform, especially at a train or metro station.

• a l’andana = on the platform / at the platform

Depending on context, andana is generally understood as the area where passengers wait for a train or similar transport.

Because Avui means today, and Catalan often uses the present tense for actions happening now or as part of today’s plan.

• Avui vaig a la ciutat = Today I’m going to the city
• Avui treballo = Today I’m working
• Avui arriben tard = Today they’re arriving late

Just like in English, the present can describe something current, scheduled, or happening today.

i simply means and.

• Avui vaig a la ciutat en tren, i la meva germana m’espera a l’andana.
• Today I’m going to the city by train, and my sister is waiting for me on the platform.

It joins the two parts of the sentence.

Yes, the word order is very normal.

The sentence follows a common pattern:

• Avui = time expression
• vaig a la ciutat en tren = main clause
• i la meva germana m’espera a l’andana = second clause

Catalan word order is often similar to English, but object pronouns usually come before the verb:

• my sister waits for me → la meva germana m’espera

That pronoun placement is one of the biggest differences.

Yes. Grammatically, it is a present-tense sentence, so a very literal translation is Today I go to the city by train. But in natural English, we would usually say:

• Today I’m going to the city by train

So the Catalan present tense can match either a simple present or a present continuous translation in English, depending on what sounds natural.

Because of the verb form and the pronoun:

• espera = he/she waits
• m’ = me

So m’espera literally means waits me, but in correct English that becomes waits for me.

If it were I wait, Catalan would use:

• espero = I wait

So the ending -a tells you it is a he/she form, not I.

Here are the main forms:

• avui = today
• vaig ← from anar = to go
• ciutat = city
• tren = train
• germana = sister
• espera ← from esperar = to wait
• andana = platform

This can help you recognize them when they appear in other sentences.