Pečicí kámen je v troubě.

It breaks down like this:

• pečicí kámen = the subject, a noun phrase
  • pečicí = adjective
  • kámen = noun
• je = is, the 3rd person singular of být (to be)
• v troubě = a prepositional phrase meaning location, literally in oven

So the structure is basically:

[subject] + [is] + [location]

That is very similar to English The baking stone is in the oven.

This is a very common Czech spelling question.

• pečicí means intended for baking / used for baking
• pečící means currently baking

So:

• pečicí kámen = a baking stone, a stone used for baking
• pečící žena = a woman who is baking

In this sentence, the stone is not doing the baking itself in the grammatical sense; it is a tool used for baking, so pečicí is the correct form.

Kámen is in the nominative singular because it is the subject of the sentence.

The basic dictionary form is kámen = stone.

Here it does not change because it is the thing being talked about:

• Pečicí kámen = the baking stone
• je v troubě = is in the oven

If the noun had a different role in the sentence, it might appear in another case.

Because the preposition v meaning in takes the locative case when it expresses location.

The noun is:

• trouba = oven

But after v for location, it changes to the locative singular:

• v troubě = in the oven

So:

• trouba = dictionary form
• v troubě = after v when you mean in the oven

This is one of the most important case patterns to get used to in Czech.

It is the locative singular.

Why?

Because v + location normally requires the locative:

• v domě = in the house
• v kuchyni = in the kitchen
• v troubě = in the oven

So in this sentence:

• trouba is a feminine noun
• its locative singular form is troubě

Because Czech does not normally use articles like English a and the.

So:

• kámen can mean a stone or the stone
• trouba can mean an oven or the oven

Which one is meant depends on context.

In this sentence, English naturally uses the: The baking stone is in the oven.
But Czech simply says Pečicí kámen je v troubě.

Yes. Czech word order is more flexible than English because case endings show grammatical relationships.

The neutral order here is:

• Pečicí kámen je v troubě.

But you could also say:

• V troubě je pečicí kámen.

That version puts more focus on where it is.

So both are possible, but they may differ slightly in emphasis:

• Pečicí kámen je v troubě. = neutral, straightforward
• V troubě je pečicí kámen. = emphasis on the location

A rough English-friendly guide is:

PEH-chi-tsee KAA-men yeh f TROU-byeh

A few important sounds:

• č sounds like ch in church
• c sounds like ts
• á is a long vowel
• ě after b makes bě, pronounced roughly byeh
• je sounds like yeh

Also, Czech stress is usually on the first syllable of each word:

• PEčicí
• KÁmen
• je
• V TROUbě

In normal pronunciation, v before a voiceless consonant often becomes devoiced.

Since the next word begins with t in troubě, many speakers pronounce:

• v troubě approximately like f troubě

This is completely normal in Czech pronunciation.

The spelling stays v, but the sound often shifts in connected speech.

Yes, in a normal full sentence it is.

Je is the present tense form of být (to be) for he/she/it.

So:

• kámen je v troubě = the stone is in the oven

Unlike in some languages, you normally do need the verb to be in this kind of Czech sentence.

You may occasionally see it omitted in headlines, notes, or very informal fragments, but in standard full Czech, je belongs here.

Yes. Trouba is the normal everyday Czech word for oven.

You may also see it in compounds or longer phrases, but by itself trouba is the usual word.

One small cultural note: in colloquial Czech, trouba can also mean idiot / dummy as an insult.
But in this sentence, it clearly just means oven because of the context v troubě.

Yes, it sounds natural.

It is a normal adjective + noun combination:

• pečicí = baking / for baking
• kámen = stone

So pečicí kámen is a natural way to say baking stone or pizza stone.

Czech often forms this kind of practical descriptive phrase with an adjective showing purpose, like:

• pečicí papír = baking paper
• pracovní stůl = work table
• kuchyňský nůž = kitchen knife

So this sentence sounds fully idiomatic.