Learn Hardcore Croatian: Liječnica danas radi u bolnici. - The female doctor is working at the hospital today.

It is the feminine form of liječnik (male doctor).
It is in nominative singular here, used as the subject of the sentence.
English usually uses gender‑neutral doctor, but Croatian often marks professions for gender.

Why is there no word for “the” before liječnica or bolnici?

Croatian has no articles (no a/an or the).

Liječnica danas radi u bolnici can mean “A doctor is working in the hospital today” or “The doctor is working in the hospital today”.
Whether it is definite or indefinite is understood from context, not from a separate word.

Why is the verb radi and not raditi?

Raditi is the infinitive form: to work.
In the sentence, the subject is she (liječnica), so you need 3rd person singular present tense:

(ona) radi = she works / she is working

So radi is simply “raditi” conjugated for she/it/he in the present.

Does radi mean both “works” and “is working”?

Yes. Croatian doesn’t have a separate “-ing” present like English.

Liječnica danas radi u bolnici can be translated as
- “The doctor works in the hospital today” or
- “The doctor is working in the hospital today”.

Context tells you whether it’s a habitual action or something happening right now/today only. The Croatian form is the same.

Why don’t we say je radi (like “is working”) in Croatian?

In Croatian, biti (to be) is not used as an auxiliary with normal verbs in the present tense.

You say ona radi (she works / she is working), not ona je radi.
Je is used
- as a copula: Ona je liječnica. – She is a doctor.
- as an auxiliary in past/future tenses: Ona je radila. – She worked / has worked.

For simple present actions, you conjugate the verb itself and don’t add “je”.

What is the base (dictionary) form of bolnici, and why does it end in -i here?

The base form is bolnica – hospital (feminine noun, nominative singular).

In u bolnici, bolnici is:

Locative singular of bolnica (ending -i is typical for many feminine -a nouns in the locative).
It’s used because we are talking about location: in the hospital.

So: bolnica (dictionary form) → u bolnici (in the hospital).

Why do we use u with bolnici, and what case does it require here?

The preposition u can take accusative or locative, depending on meaning:

u + accusative = movement into something
- Idem u bolnicu. – I’m going into the hospital.
u + locative = location inside something
- Radim u bolnici. – I work in the hospital.

In Liječnica danas radi u bolnici, there is no movement, only location, so u takes the locative → bolnici.

Can we say na bolnici instead of u bolnici?

Normally no.

U bolnici = in/at the hospital (as a place of work or treatment) – this is what you want here.
Na is used with some places (e.g. na poslu – at work, na fakultetu – at the faculty, na stanici – at the station), but with “hospital” the normal choice is “u bolnici”.

Na bolnici would literally suggest on top of the hospital building and sounds wrong in this context.

Where can danas go in the sentence, and does the word order change the meaning?

All of these are grammatical:

Liječnica danas radi u bolnici. (neutral, very natural)
Danas liječnica radi u bolnici. (emphasizes today a bit more)
Liječnica radi danas u bolnici. (slight emphasis on today, still OK)
Liječnica radi u bolnici danas. (unusual, but possible in spoken language, stressing today at the end)

The basic meaning stays the same (she is working at the hospital today); changes in order mainly affect emphasis / focus, not grammar.

Could we also say Ona danas radi u bolnici with the pronoun ona?

Yes, you can.

Ona danas radi u bolnici. – She is working at the hospital today.

However:

Croatian often drops subject pronouns because the verb ending shows the person: radi = he/she works.
If you say Ona danas radi u bolnici, you are slightly emphasising “she” (e.g. She is working there today, not someone else).

In the neutral case, Liječnica danas radi u bolnici is more typical.

How would the sentence change if the doctor were male or if there were several doctors?

Male doctor (singular):

Liječnik danas radi u bolnici. – The (male) doctor is working at the hospital today.

Female doctors (plural):

Liječnice danas rade u bolnici. – The (female) doctors are working at the hospital today.

Male (or mixed) group of doctors (plural):

Liječnici danas rade u bolnici. – The doctors are working at the hospital today.

Notice the changes:

Subject noun: liječnica → liječnik / liječnice / liječnici
Verb: radi → rade for plural.

Are there other common words for “doctor” in Croatian, like doktor/doktorica?

Yes. Two main sets:

liječnik / liječnica – medical doctor (very standard and common)
doktor / doktorica – can mean
- medical doctor in everyday speech, and
- a person with a PhD / doctorate.

In this sentence, you could also say:

Doktorica danas radi u bolnici. – The (female) doctor is working at the hospital today.

It sounds a bit more colloquial, but is widely used.

How do you pronounce liječnica, and what do the special letters mean?

Liječnica is pronounced approximately like: LYEH-ch-nee-tsa.

Letter notes:

lj = a single sound [ʎ], like the lli in Italian famiglia, somewhat like lli in English million.
je here sounds roughly like ye in yes.
č = hard ch as in church.
c (in -nica) = ts sound, like ts in cats.

Stress is usually on the first syllable: LJEČ-nica (in standard pronunciation).

What tense is radi, and how do you conjugate raditi in the present?

Radi is present tense, 3rd person singular of raditi (to work).

Present tense of raditi:

ja radim – I work
ti radiš – you (sg.) work
on/ona/ono radi – he/she/it works
mi radimo – we work
vi radite – you (pl./formal) work
oni/one/ona rade – they work

In the sentence, liječnica … radi matches ona radi (she works).