Ventilek je v ráfku.

to be

Breakdown of Ventilek je v ráfku.

• v: in
• ventilek: the tyre valve
• ráfek: the wheel rim

Questions & Answers about Ventilek je v ráfku.

Why is it v ráfku and not v ráfek?

Because after v when it means in/inside, Czech normally uses the locative case.

• dictionary form: ráfek
• locative singular: ráfku

So:

• ráfek = rim
• v ráfku = in the rim

This is one of the first big differences from English: Czech changes noun endings depending on their role in the sentence.

What case is ráfku?

Ráfku is singular locative.

The preposition v often takes:

• locative for location: in, inside, at
• accusative for motion into something

Here the sentence describes a location, not movement, so locative is used:

• Ventilek je v ráfku. = The valve is in the rim.
• Compare: Dám ventilek do ráfku. = I’ll put the valve into the rim.

Why is there je? Can Czech leave it out?

Here je is the 3rd person singular of být = to be.

• ventilek = the subject
• je = is
• v ráfku = in the rim

So the structure is very similar to English: The valve is in the rim.

In the present tense, Czech usually does use je in this kind of sentence. It is not normally omitted here.