Normalmente tardo media hora en llegar a la universidad en autobús.

Yes. In this kind of sentence, tardar means to take time.

So:

• Tardo media hora = It takes me half an hour / I take half an hour

Spanish often uses tardar where English uses it takes.

More examples:

• Tardo diez minutos en cocinar. = It takes me ten minutes to cook.
• ¿Cuánto tardas? = How long do you take?

Here, tardo is the 1st person singular present tense: I take / I usually take.

Media hora is the normal way to say half an hour.

• media hora = half an hour
• una hora y media = an hour and a half

You may sometimes hear una media hora, but that often sounds more like about half an hour or a less exact estimate. In a neutral statement like this, media hora is the most natural choice.

After tardar + time expression, Spanish normally uses en + infinitive to say to take time to do something.

Structure:

• tardar + amount of time + en + infinitive

So:

• Tardo media hora en llegar = It takes me half an hour to arrive / to get there

More examples:

• Tardo cinco minutos en vestirme. = It takes me five minutes to get dressed.
• Tardamos dos horas en terminar. = It took us two hours to finish.

This is a very common pattern, so it is worth memorising.

Normally, no. With tardar, the standard construction is en + infinitive, not para + infinitive.

So:

• Tardo media hora en llegar. ✅
• Tardo media hora para llegar. ❌

English speakers often want to use para because they think of to arrive, but after tardar, Spanish wants en.

The verb llegar usually needs a before the destination.

So:

• llegar a casa
• llegar al trabajo
• llegar a la universidad

That is just how llegar works: llegar a + place = to arrive at / get to + place

Notice the contraction rule too:

• a + el = al
• but a + la stays a la

So:

• llegar al museo
• llegar a la universidad

In Spanish, places like la universidad, el trabajo, el colegio, la oficina often use the definite article.

So Spanish says:

• a la universidad
• al trabajo
• a la oficina

Even though English often says just to university or to work, Spanish commonly keeps the article.

Yes. En autobús means by bus.

Spanish often uses en + transport to talk about how you travel:

• en autobús = by bus
• en tren = by train
• en coche = by car
• en avión = by plane

So in this sentence:

• en llegar a la universidad en autobús

the first en belongs to tardar en + infinitive, and the second en means by with transport.

Because en autobús means by bus in a general sense: the mode of transport.

Compare:

• Voy en autobús. = I go by bus.
• Estoy en el autobús. = I am on the bus.

So:

• en autobús = by bus, using bus transport generally
• en el autobús = on the bus, referring to a specific bus or being physically inside it

In your sentence, the idea is transport method, so en autobús is correct.

Normalmente means normally / usually.

It tells you this is a habitual action, not necessarily something happening right now. So the present tense here has a habitual meaning:

• Normalmente tardo... = I usually take...

You could also place it elsewhere:

• Tardo normalmente media hora...

But putting normalmente at the beginning is very natural and common.

Spanish often leaves out subject pronouns when the verb already shows who the subject is.

Here, tardo clearly means I take, so yo is unnecessary.

• (Yo) tardo media hora...

Both are grammatically correct, but omitting yo is more natural unless you want emphasis or contrast.

For example:

• Yo tardo media hora, pero mi hermano tarda una hora.

There, yo is useful because you are contrasting two people.

Yes. Tardo is the present indicative of tardar.

In this sentence, the present tense expresses a routine or usual fact:

• Normalmente tardo media hora... = I usually take half an hour...

This is very similar to the English present simple for habits:

• I usually take...

Both can be possible, but they focus on slightly different things.

• tardar ... en llegar a la universidad = time it takes to get there / arrive
• tardar ... en ir a la universidad = time it takes to go to university

In many everyday contexts, both are understandable. But with travel time, tardar en llegar is extremely common because it focuses on reaching the destination.

So your original sentence sounds very natural.

Because the stress falls on the last syllable: au-to-BÚS.

In Spanish spelling, words ending in s are normally stressed on the second-to-last syllable unless there is an accent mark. Since autobús is stressed on the last syllable, it needs the written accent.

Its plural is:

• autobuses

and then the accent disappears because the stress pattern changes naturally.

You can keep the same structure and just change the verb form, the time expression, or the destination.

Pattern:

• Normalmente + tardar (conjugated) + time + en + infinitive + destination + transport

Examples:

• Normalmente tardo veinte minutos en llegar al trabajo en coche.
• Normalmente tardas una hora en llegar al centro en tren.
• Normalmente tardamos quince minutos en llegar al colegio a pie.

Useful forms of tardar:

• tardo = I take
• tardas = you take
• tarda = he/she takes
• tardamos = we take
• tardáis = you all take
• tardan = they take

Yes, it sounds very natural in Spain.

A few notes:

• autobús is standard and very common in Spain.
• la universidad is also completely natural.
• The whole sentence is normal everyday Spanish.

In some other Spanish-speaking countries, people might also say bus, camión, guagua, etc., depending on the region, but autobús is perfectly standard Spanish and especially suitable for Spain.