Zubni kamenac je na zubu.

to be

Breakdown of Zubni kamenac je na zubu.

• na: on
• zub: a tooth
• zubni kamenac: dental tartar

Questions & Answers about Zubni kamenac je na zubu.

Why is it na zubu and not na zub?

Because na can take different cases depending on the meaning:

• na + locative = on, at a location
• na + accusative = movement onto something

Here the sentence describes a location: the tartar is on the tooth, so Serbian uses the locative case:

• zub = tooth
• na zubu = on the tooth

Compare:

• Kamenac je na zubu. = The tartar is on the tooth.
• Stavljam nešto na zub. = I am putting something onto the tooth.

Why does zub become zubu?

Because zub is in the locative singular after na when it means location.

The base form is:

• zub = tooth

The locative singular is:

• zubu = on/in/about the tooth, depending on the preposition

So:

• na zubu = on the tooth

This -u ending is very common for masculine and neuter nouns in the locative singular.

What exactly does zubni kamenac mean?