Putnik ide autobusom u grad.

Croatian has no articles at all, so it doesn’t use words like a/an or the.
The bare nouns putnik and grad can mean:

• putnik → a passenger / the passenger / a traveler / the traveler
• grad → a city / the city / (the) town

Whether you translate with a or the in English depends only on context, not on anything in the Croatian form.

Autobusom is the instrumental singular of autobus (bus).

• Nominative: autobus – a bus / the bus
• Instrumental: autobusom – with a bus / by bus

Croatian uses the instrumental case to show means or instrument, including means of transport.
So:

• ići autobusom = to go by bus
• ići vlakom = to go by train
• ići avionom = to go by plane

The ending -om on autobusom signals that instrumental meaning.

Croatian uses different cases with u depending on whether it’s movement or location:

• u + accusative (u grad) → movement into something

  • Putnik ide u grad. = The passenger is going to (into) the city.

• u + locative (u gradu) → location in something

  • Putnik je u gradu. = The passenger is in the city.

So u grad (accusative) answers “Where to?” (direction), while u gradu (locative) answers “Where (at)?” (position).

Ide is:

• 3rd person singular
• present tense
• of the verb ići (to go).

Basic present-tense forms of ići:

• ja idem – I go / am going
• ti ideš – you go
• on/ona/ono ide – he/she/it goes
• mi idemo – we go
• vi idete – you (pl./formal) go
• oni/one/ona idu – they go

So ide simply means (he/she/it) goes / is going.

Yes, you can change the order; Croatian word order is quite flexible. All of these are grammatically fine:

• Putnik ide autobusom u grad.
• Putnik ide u grad autobusom.
• Autobusom putnik ide u grad.
• U grad putnik ide autobusom.

The basic meaning is the same: The passenger is going by bus to the city.

Changing the order mainly affects emphasis and what is “new” information:

• Starting with Autobusom highlights the means of transport.
• Starting with U grad highlights the destination.

For a beginner, Putnik ide autobusom u grad or Putnik ide u grad autobusom are the most neutral.

Yes, putnik is grammatically masculine and typically refers to a male passenger/traveler, or a person of unspecified gender when gender isn’t important.

The feminine form is:

• putnica – female passenger / female traveler

Examples:

• Putnik ide autobusom u grad. – The (male / generic) passenger is going by bus to the city.
• Putnica ide autobusom u grad. – The female passenger is going by bus to the city.

Putnik can mean both passenger and traveler, depending on context:

• On public transport (bus, train, plane), putnik is most often understood as passenger.
• In a broader, more general sense (someone traveling somewhere), it can be traveler.

If you specifically want to emphasize traveler in a more “touristy” or long-journey sense, you might also see:

• putnik – traveler/passenger (very common, neutral)
• putnik namjernik – a wayfarer, traveler passing through (a bit stylistic/old-fashioned)

For everyday modern speech with buses, trains, etc., putnik is the standard word.

Not if you mean by bus.

• autobusom (instrumental on its own) expresses means of transport → by bus.
• s/sa + autobusom literally means with the bus (together with the bus, accompanied by the bus as an object), which is not how you say by bus.

So:

• Putnik ide autobusom u grad. – correct: The passenger is going by bus to the city.
• Putnik ide s autobusom u grad. – sounds like he is going “together with the bus” (odd or wrong in normal usage).

Yes, you can say:

• Putnik putuje autobusom u grad.

This is grammatically correct and natural.

Difference:

• ići = to go (very general, covers walking, driving, etc.; focuses on movement or going somewhere)
• putovati = to travel (slightly more “journey”-like, often for longer or more formal trips, though it can also be used for shorter ones)

Nuance:

• Putnik ide autobusom u grad. – more neutral: he is going to the city by bus.
• Putnik putuje autobusom u grad. – sounds a bit more like “he is traveling by bus to the city” (emphasizing the trip itself, not just the simple act of going).

In this context, Croatian normally uses:

• u with cities, towns, villages, countries, buildings, closed spaces:

  • u grad – to the city
  • u Zagreb – to Zagreb
  • u školu – to (the) school
  • u kuću – into the house

• na is used with many open areas, surfaces, events, institutions, islands, etc.:

  • na selo – to the countryside
  • na posao – to work
  • na more – to the seaside
  • na kolodvor – to the station
  • na koncert – to a concert

For going to a city/town, the standard is u grad, not na grad.

You would change:

• the verb ide (is going) to je (is), and
• u grad (accusative: to the city) to u gradu (locative: in the city).

Examples:

• Putnik ide autobusom u grad. – The passenger is going by bus to the city.
• Putnik je u gradu. – The passenger is in the city.

If you also wanted to keep the bus, you’d need more context, e.g.:

• Putnik je u gradu i vozi se autobusom. – The passenger is in the city and is riding the bus.

Approximate guides for English speakers:

• putnik → POOT-neek

  • u like “oo” in book (but slightly longer)
  • tn is a clear consonant cluster, no extra vowel in between.

• ide → EE-deh

  • i like “ee” in see
  • e like “e” in met.

• autobusom → OW-too-boh-som

  • au is like saying “a” + “u” quickly: similar to “ow” in cow but smoother.
  • Each vowel is pronounced clearly: a-u-to-bu-som.

• grad → grahd

  • r is rolled or tapped (like many Spanish or Italian r’s).
  • Final d is pronounced (not silent).

All vowels are short and clear, and each written vowel is pronounced.