Kajak se může převrhnout v peřeji.

Here se is part of the verb převrhnout se / převrhnout in the sense of to capsize / to tip over.

In Czech, se often makes a verb reflexive or gives it an intransitive meaning. In this sentence, the kayak is not flipping something else; it is itself turning over. So se helps express that idea.

Compare:

• Převrhnout kajak = to overturn a kayak (something overturns it)
• Kajak se převrhne = the kayak overturns / capsizes

So se is very natural here and is not translated word-for-word into English.

Because může is a modal verb, meaning can / may / is able to, and modal verbs in Czech are followed by an infinitive.

So the structure is:

• může = can / may
• převrhnout = infinitive, to overturn / to capsize

This is parallel to English:

• The kayak can capsize

not

• The kayak can capsizes

The same pattern appears with other Czech modals too:

• musí jet = must go
• chce plavat = wants to swim
• nemůže přijít = cannot come

Může is the 3rd person singular form of moci (to be able to / can), because the subject is kajak, which is singular.

A few forms of moci:

• já můžu / mohu = I can
• ty můžeš = you can
• on/ona/ono může = he/she/it can

Since kajak is grammatically masculine inanimate singular, Czech uses the same verb form as for he/it: může.

In this sentence, převrhnout (se) means something like:

• to tip over
• to overturn
• to capsize

With boats or kayaks, capsize is often the most natural English equivalent.

It comes from the idea of turning over from an upright position. In everyday Czech, it can also be used for other things, not only boats:

• Sklenice se převrhla. = The glass tipped over.
• Loď se převrhla. = The boat capsized.

V peřeji is in the locative case because it follows the preposition v meaning in.

The preposition v often requires the locative when it expresses location:

• v domě = in the house
• v řece = in the river
• v peřeji = in the rapid

So here:

• peřej = rapid
• v peřeji = in a rapid / in the rapids depending on context

The basic dictionary form is peřej.

In the sentence, it appears as peřeji, which is the singular locative form after v.

So:

• peřej = nominative singular
• v peřeji = locative singular

This noun can be tricky because it is not one of the most familiar Czech noun patterns for beginners.

In Czech, v peřeji is grammatically singular.

Even though English often uses the plural rapids, Czech can use the singular peřej to refer to a rapid section of water. So you should not expect the number to match English exactly.

If Czech wanted a plural form, that would be a different structure. But in this sentence, v peřeji is singular and perfectly normal.

Yes, Czech word order is relatively flexible, and other orders are possible. The given sentence is a neutral, natural order.

Current order:

• Kajak = topic/subject
• se může převrhnout = verbal part
• v peřeji = place

You could also hear variations such as:

• V peřeji se může kajak převrhnout.
• Kajak se v peřeji může převrhnout.

These versions shift emphasis slightly. Czech often moves elements around to highlight what is new, important, or contrastive.

But for a learner, the original sentence is a good standard pattern.

This is because se is a clitic in Czech. Clitics are short unstressed words that tend to go in a specific position in the sentence, usually near the beginning of the clause, rather than staying next to the infinitive they belong to logically.

So Czech says:

• Kajak se může převrhnout.

not usually

• Kajak může převrhnout se.

That second version sounds wrong in normal Czech.

This is a very important Czech word-order habit: little words like se, si, mi, ti, ho, mu often appear early in the sentence.

Usually it is most naturally understood as can, meaning it is possible for the kayak to capsize.

So the sentence suggests possibility:

• The kayak can capsize in a rapid.

Depending on context, může can sometimes also mean may, but here can is the best default interpretation.

A rough pronunciation guide is:

Kajak se může převrhnout v peřeji
KAH-yak se MOO-zheh PRZHEH-vr-hnout f PEH-rzheh-yi

A few useful notes:

• j in Czech is like English y
• ž sounds like the s in measure
• ř is the famous Czech sound, something like a rolled/trilled r mixed with zh
• ch is like the ch in German Bach or Scottish loch
• v is often pronounced close to f before a voiceless consonant, so v peřeji may sound a bit like f peřeji

If ř is hard, that is normal for learners. It takes time.

Kajak is a noun, and it is masculine inanimate.

That matters because Czech grammar depends heavily on gender. Here, the gender does not change the form of může, but it would matter in adjectives and past tense forms.

For example:

• ten kajak = that kayak
• nový kajak = a new kayak
• kajak se převrhl = the kayak capsized (past tense masculine inanimate form)

Yes, that would also be possible in many contexts.

Both převrhnout se and převrátit se can refer to overturning or capsizing. The exact nuance may vary a little by speaker or context, but both are understandable and natural.

Learners should mainly notice that Czech often has more than one verb for a similar physical action, and usage can depend on style, context, and habit.