Controllo il biglietto prima di prendere il treno.

Controllo is the first-person singular present tense of controllare.

• controllare = to check
• controllo = I check

So the sentence uses a fully conjugated verb because the speaker is saying what I do:

• Controllo il biglietto = I check the ticket

If you used controllare, it would be the infinitive to check, not a complete main verb here.

Italian often omits subject pronouns when they are clear from the verb ending.

• controllo already tells you the subject is I
• so io is not necessary

You could say:

• Io controllo il biglietto...

but that usually adds emphasis, contrast, or clarity. In normal speech, Controllo il biglietto... sounds completely natural.

Italian uses the definite article much more often than English.

So il biglietto literally means the ticket, but in context it can naturally correspond to my ticket, the ticket, or just the ticket I’m using.

Italian often prefers the article where English might leave it out or use a possessive:

• Controllo il biglietto = I check the ticket / my ticket

This is very normal Italian.

Because in Italian, when prima is followed by a verb, you normally use:

• prima di + infinitive

So:

• prima di prendere il treno = before taking the train / before I take the train

Compare:

• prima del viaggio = before the trip
  Here it is followed by a noun, not a verb.

So the pattern is:

• prima di + verb
• prima di uscire
• prima di mangiare
• prima di prendere il treno

After the preposition di, Italian uses the infinitive if the subject stays the same.

So:

• Controllo il biglietto prima di prendere il treno

means:

• I check the ticket before taking the train
• literally: before to take the train

Because the person who checks the ticket is also the person who takes the train, Italian uses the infinitive prendere.

If the subject changed, Italian would normally use a different structure, for example:

• Controllo il biglietto prima che lui prenda il treno
  = I check the ticket before he takes the train

Again, Italian usually keeps the article with nouns like this.

• prendere il treno = to take the train

This is the normal expression. English often drops or changes articles differently, but in Italian il treno is standard.

You will see this with many transport expressions:

• prendere l’autobus
• prendere il taxi
• prendere la metropolitana

It most directly means to take the train, but depending on context, English may translate it as catch the train, get the train, or go by train.

In this sentence, the idea is simply that the speaker checks the ticket before boarding or traveling by train.

So prendere il treno is a very common everyday expression for using the train as transport.

It can do either, depending on context.

Italian present tense often covers:

• a habit/routine
  
  • Controllo il biglietto prima di prendere il treno
    = I check my ticket before taking the train
• something happening now
• sometimes even a near-future idea

Without extra context, many learners would understand this as a habitual action or a general statement about what the speaker does.

Yes, absolutely.

Both are correct:

• Controllo il biglietto prima di prendere il treno.
• Prima di prendere il treno, controllo il biglietto.

The difference is mainly focus and word order:

• starting with Controllo il biglietto emphasizes the main action first
• starting with Prima di prendere il treno emphasizes the time sequence first

Both are natural.

Yes, controllo is very natural here.

• controllare = to check
• verificare = to verify

Both can work in some contexts, but controllare il biglietto sounds very everyday and idiomatic for checking that you have the right ticket, that it’s with you, or that everything is in order.

Verifico il biglietto is possible, but it can sound a little more formal or technical depending on context.

A simple pronunciation guide is:

con-TROL-lo il bil-LYET-to PREE-ma di PREN-de-re il TRE-no

A few useful notes:

• gli in biglietto is a sound English speakers often find tricky
• tt in biglietto is pronounced more strongly than a single t
• stress falls on:
  • contRÓLlo
  • bigliÉtto
  • prÉndere
  • trÉno

If you say it smoothly, it sounds like:

Controllo il biglietto prima di prendere il treno.

Yes, but the meaning changes slightly.

• prendere il treno = to take the train
• salire sul treno = to get on the train / board the train

So:

• prima di prendere il treno refers more generally to taking that train journey
• prima di salire sul treno focuses more specifically on the moment of boarding

Both can be correct, but they are not exactly identical.