Maybe this will help:
1. Zvonimir je u svojoj sobi. (<em>Zvonimir is in his room</em>.)
1) Tko je u svojoj sobi? (<em>Who is in his/her room?</em>) - Zvonimir.
- The nominative case answers the questions tko? (animate; <em>who?</em>) and što? (inanimate; <em>what?</em>).
- Zvonimir is the answer to <em>who?</em>, therefore it's in the nominative case.
2) U čemu je Zvonimir? (<em>What is Zvonimir in?</em>) - U svojoj sobi. (<em>In his room.</em>)
- The locative case answers the questions u komu? (<em>in whom?</em>) or u čemu? (<em>in what?</em>).
- U svojoj sobi is the answer to <em>in what?</em>, therefore it's in the locative case.
- If you ask the question Gdje je Zvonimir? (<em>Where is Zvonimir</em>?) you can't find out the case of a noun, because various prepositions (<em>in, on, at, around, above, below, ...</em>) go with different cases. The preposition u (<em>in</em>) can go with the accusative and locative cases, depending on the meaning. If it went with the accusative case, it would express motion towards something, for example: Zvonimir ide u svoju sobu. (<em>Zvonimir is going to his room. - </em>u svoju sobu is dative).
2. Domagoj ide kući biciklom. (<em>Domagoj is going home by bike.</em>)
1) Tko ide kući biciklom? (<em>Who is going home by bike?</em>) - Domagoj.
- Domagoj is in the nominative case.
2) Čime Domagoj ide kući? (<em>Domagoj is going home using what?</em>) - Biciklom. (<em>By bike.</em>)
- Bicikl > biciklom -- instrumental.
Exercises.
Determine the grammatical case of the underlined nouns in the following sentences:Not at all, if you have any questions, feel free to ask me.
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Exercises.
Determine the grammatical case of the underlined nouns in the following sentences:
Zvonimir je u svojoj sobi. (Zvonimir is in his room.)
----I ask: WHERE he is? : This is LOKATIVE case, right?
Domagoj ide kući biciklom. (Domagoj is going home by bike.)
------I ask: With whom? This is INSTRUMENTAL case, right?
Hrvatska je pobijedila na nogometnom natjecanju. (Croatia won the football tournament.)
------------I DONT UNDERSTAND THIS
UNDERLINED WORDS
A ) in first sentence:
Zvonimir - svojoj - sobi
B) in the second sentence
Domagoj - kući - biciklom;
C ) and in the third:
Hrvatska - nogometnom - natjecanju
Thanks for help me!