Moja četkica za zube je u kupaonici.

My toothbrush is in the bathroom.

Breakdown of Moja četkica za zube je u kupaonici.

• biti: to be
• u: in
• moj: my
• kupaonica: bathroom
• četkica za zube: toothbrush

Questions & Answers about Moja četkica za zube je u kupaonici.

Why is it moja četkica and not moj četkica or moje četkica?

In Croatian, the possessive moj / moja / moje must agree in gender, number, and case with the noun it modifies.

• četkica is a feminine singular noun (its basic form ends in -a).
• So the correct form is moja četkica (feminine singular nominative).
• moj is masculine, moje is neuter (or feminine plural), so they would not agree with četkica here.

What does the -ica ending in četkica mean, and is there a difference between četka and četkica?

The ending -ica often forms a diminutive (a “smaller” or more specific version of something).

• četka = a brush (general: hairbrush, cleaning brush, etc.).
• četkica = a small brush, literally “little brush”.

In practice, četkica za zube is the normal, standard way to say toothbrush, not četka za zube. A Croatian speaker will almost always use četkica in this phrase.

Why is it četkica za zube and not something like zubna četkica or moja četkica zubi?

All of these are possible structures, but they are not equally common or natural:

• četkica za zube

  • Literally: “brush for teeth”.
  • This is the most common, everyday way to say toothbrush.
  • za (“for”) is followed by the accusative plural zube.

• zubna četkica

  • Literally: “dental brush / tooth brush”, using the adjective zubna (“dental, tooth-”).
  • Grammatically correct and understandable, but sounds a bit more technical or formal, less idiomatic in casual speech.

• moja četkica zubi

  • This is incorrect. If you want “brush of teeth”, you need the genitive plural: četkica zuba.
  • Even četkica zuba is grammatically possible but sounds unusual; people strongly prefer četkica za zube.

What case is zube, and why not zubi or zubima?

zube is the accusative plural of zub (“tooth”).

• The preposition za (“for”) is normally followed by the accusative case.
• zubi is nominative plural (“teeth” as the subject).
• zubima is dative/locative/instrumental plural (“to/at/with the teeth”).

In četkica za zube, the za forces the accusative, so you must say zube, not zubi or zubima.

What case is kupaonici, and what is the base form of that noun?

The base (dictionary) form is kupaonica (“bathroom”), which is feminine.

The form kupaonici is locative singular. It appears because:

• The preposition u (“in”) + a static location normally uses the locative case.
• So: u kupaonici = “in the bathroom” (location, no movement).

Why do we say u kupaonici and not u kupaonicu?

The choice depends on whether there is movement or not:

• u

  • locative = location (where something/someone is).
  • Moja četkica za zube je u kupaonici.
    “My toothbrush is in the bathroom.” (no movement)

• u

  • accusative = direction / movement into.
  • Idem u kupaonicu.
    “I am going into the bathroom.”

So in your sentence, you want a static location, so u kupaonici (locative) is correct.

Why u kupaonici and not na kupaonici? What is the difference between u and na?

Both u and na can mean something like in / at, but they are used with different kinds of nouns and spatial concepts:

• u = in, inside, within an enclosed space

  • u kupaonici – in the bathroom (inside the room)
  • u sobi – in the room
  • u školi – at/in school (inside the building)

• na = on, on top of, or at an open/flat place or event

  • na stolu – on the table
  • na plaži – on the beach
  • na koncertu – at a concert

A bathroom is thought of as an enclosed space, so you use u kupaonici, not na kupaonici.

Could I also say U kupaonici je moja četkica za zube? Does the word order change the meaning?

Yes, you can say:

• Moja četkica za zube je u kupaonici.
• U kupaonici je moja četkica za zube.

Both are grammatically correct and mean the same basic thing. The difference is in focus/emphasis:

• Starting with Moja četkica za zube emphasizes what you are talking about (the toothbrush), then you say where it is.
• Starting with U kupaonici puts more focus on the place, as if you are answering “Where is it?” or contrasting it with some other location.

In everyday speech, both orders sound natural; context and intonation give the nuance.

Can I say Moja je četkica za zube u kupaonici? Why is je in the middle?

Yes, this is also correct:

• Moja je četkica za zube u kupaonici.

Here, the verb je is “split” into the second position in the sentence. Croatian has a tendency to place short, unstressed words (like je) in early positions, often second.

This structure is often used to put contrastive or special emphasis on moja (“my”):

• Implied contrast: “My toothbrush is in the bathroom (maybe someone else’s isn’t).”

So you have three natural variants:

• Moja četkica za zube je u kupaonici.
• Moja je četkica za zube u kupaonici.
• U kupaonici je moja četkica za zube.

Is the verb je (“is”) required here? Could I just say Moja četkica za zube u kupaonici?

In standard Croatian, the verb je is required in this kind of sentence.

• Moja četkica za zube je u kupaonici. – correct, normal.
• Moja četkica za zube u kupaonici. – sounds incomplete or like a broken/telegraphic sentence.

Unlike Russian, for example, Croatian normally does not drop the present tense of biti (“to be”) in simple “X is Y” sentences. You might see je omitted in headlines, notes, or very colloquial speech, but for proper grammar and clear speech, keep je.

Why is moja used at all? Since it’s my toothbrush, could Croatian just say Četkica za zube je u kupaonici?

Yes, you can say:

• Četkica za zube je u kupaonici.

This simply means “The toothbrush is in the bathroom” (or “A toothbrush is in the bathroom”, depending on context), without specifying ownership.

Croatian has no articles like the or a, so possessives like moja often carry information that in English would partly come from the vs a vs my. Whether you include moja depends on:

• Do you need to emphasize that it is your toothbrush (not someone else’s)?
• Is it already clear from context whose toothbrush you’re talking about?

If ownership is obvious, Croatians may omit moja in casual speech.

How would I say “My toothbrushes are in the bathroom”? How does the sentence change in the plural?

You would say:

• Moje četkice za zube su u kupaonici.

Changes compared to the singular:

• moja četkica → moje četkice

  • četkica → četkice (plural noun)
  • moja → moje (feminine plural form of “my”, agreeing with četkice)

• je → su

  • je = “is” (3rd person singular)
  • su = “are” (3rd person plural), agreeing with četkice.

The rest (za zube, u kupaonici) stays the same.

Why is it moja and not moju or mojom here?

moja is in the nominative case, because it is the subject of the sentence together with četkica:

• Moja četkica za zube (who/what?) = subject → nominative.
• So you use moja (feminine nominative singular) to match četkica.

Other forms:

• moju – accusative (or sometimes vocative) feminine singular, used for a direct object.

  • Example: Vidim moju četkicu za zube. – “I see my toothbrush.”

• mojom – instrumental or locative feminine singular.

  • Example: S mojom četkicom za zube. – “With my toothbrush.”

In your sentence, you need nominative, so moja is correct.

Are there other common words for “bathroom” in Croatian, or is it always kupaonica?

Yes, there are several words, and usage can be regional:

• kupaonica – neutral, standard Croatian for “bathroom”.
• kupatilo – also very common, especially in some regions; also means “bathroom”.
• banja – used in some dialects/regions (and in other ex‑Yugoslav languages), but not standard in all varieties of Croatian.

In a standard textbook context, kupaonica (and thus u kupaonici) is a very safe and correct choice.