Learn Hardcore Turkish: Sen konuşurken kimsenin seni bölmemesini istiyorum. - While you are speaking, I want nobody to interrupt you.

İstiyorum already tells us “I (ben) want”.
In sen konuşurken, the -ken part implies “while you are speaking” anyway, because it matches the understood subject from context.

So both:

Sen konuşurken kimsenin seni bölmemesini istiyorum.
Konuşurken kimsenin seni bölmemesini istiyorum.

are grammatically correct.

Using sen adds emphasis or clarity, similar to saying:

“When you are speaking, I don’t want anyone interrupting you.”

It can stress that we are talking especially about you, not just anyone.

What does -ken in konuşurken mean exactly?

The suffix -ken means “while / when (doing something)” and attaches to the present continuous stem of the verb.

konuş- = to speak
konuşuyor = is speaking
stem used before -ken: konuşur/konuşuyor → konuşur + ken → konuşurken
(In practice you learn it as “verb stem + (y)orken / -rken / -ken” depending on the verb.)

So:

Sen konuşurken ≈ “While you are speaking / When you are speaking”

Other examples:

Ben çalışırken beni arama. – Don’t call me while I’m working.
O uyurken çok gürültü yapma. – Don’t make a lot of noise while he/she is sleeping.

-ken describes a background, ongoing action that overlaps with another action.

Why is it kimsenin and not just kimse?

Kimse means “nobody / anybody”, depending on context and negation.

Here, we need kimse in the genitive case (the “of” form), because it forms a possessive-like structure with the verbal noun:

kimse → kimse-nin = “of nobody / nobody’s”

The structure is:

kimsenin seni bölmemesi
literally: “the not-interrupting-you of nobody”
→ more naturally: “nobody interrupting you”

This is a common pattern in Turkish:

Ali’nin gelmesi – Ali’s coming / the fact that Ali comes
Öğrencilerin konuşması – the students’ speaking / the students talking
Kimsenin seni bölmemesi – nobody’s interrupting you

So kimsenin is required because bölmemesi is working like a noun (“not interrupting”), and kimsenin shows who is (not) doing that action.

Why is it seni, not sen or sana?

Bölmek (in this sense) means “to interrupt” someone, and that someone is a direct object in Turkish, so it normally takes the accusative case.

sen = you (subject / base form)
seni = you (accusative object)
sana = to you (dative)

We want “interrupt you”:

seni bölmek – to interrupt you

So inside the bigger phrase:

kimsenin seni bölmemesi
= “nobody’s not interrupting you / nobody interrupting you”

seni is the object of bölmemesi (“the not-interrupting-you of nobody”).

What exactly is inside bölmemesini? It looks very long.

Bölmemesini packs several meanings into one word. Let’s break it down:

böl- – root: to split / to interrupt
-me- – negative marker: “not”
-me- – verbal noun / nominalizer combined with the negative (gives an -meme- chunk: “not V-ing”)
-si – 3rd person singular possessive: “his/her/its/their V-ing”
-(n)i – accusative case: marks the whole phrase as the object of another verb

So:

böl-me-me-si-ni
- bölme – “interrupting” (as a noun)
- bölmeme – “not interrupting”
- bölmemesi – “his/her/its/nobody’s not interrupting” = “the fact that (someone) does not interrupt”
- bölmemesini – that fact, in accusative (because it’s what you want)

Putting it with its “owner”:

kimsenin bölmemesi – nobody’s not interrupting / the fact that nobody interrupts
kimsenin seni bölmemesini istiyorum. – I want that (I want the fact that nobody interrupts you).

Why does bölmemesi have a 3rd person possessive ending (-si) when the subject seems to be kimse?

In Turkish, when you turn a verb into a noun clause with -me / -ma, it normally takes a possessive ending that matches the clause’s subject.

Examples:

Benim gelmem – my coming
Senin gelmen – your coming
Onun gelmesi – his/her coming
Ali’nin gelmesi – Ali’s coming

For 3rd person subjects (he/she/it, names, or things like kimse), the ending is -si / -sı / -su / -sü.

So:

kimsenin seni bölmesi – “nobody’s interrupting you” (theoretically, but in practice this would need negation, see below)
kimsenin seni bölmemesi – “nobody’s not interrupting you” → “nobody interrupting you”

So -si does not mean “his/her” here; it’s just the standard 3rd-person possessor ending for this kind of nominalized verb clause with a 3rd-person subject.

Why does bölmemesini end with -ni? What is that extra -n-?

The last part -ni is actually:

buffer consonant -n-
- accusative -i

We are adding the accusative case -(y)i / -(y)ı / -(y)u / -(y)ü to a word that already ends in a vowel (bölmemesi), so we need a buffer consonant to make pronunciation easier. For 3rd person possessives, that buffer is n.

Pattern:

arabası (his/her car) → arabası-n-ı (accusative)
çocuğu (his/her child) → çocuğu-n-u

Similarly:

bölmemesi → bölmemesi-n-i

Grammatically, -i is the accusative, but it appears as -ni after a 3rd-person possessive form.

Why is the negation on bölmemesini and not on istiyorum? What is the difference between:
Kimsenin seni bölmemesini istiyorum.
and
Kimsenin seni bölmesini istemiyorum.

This is a very important contrast. Where you put the negation changes the meaning:

Kimsenin seni bölmemesini istiyorum.
- Negation is on bölmemesini (the interrupting).
- Literally: “I want the fact that nobody interrupts you.”
- Natural English: “I want nobody to interrupt you.” / “I want you not to be interrupted by anyone.”
Kimsenin seni bölmesini istemiyorum.
- Negation is on istemiyorum (want).
- Literally: “I do not want the fact that somebody / anybody interrupts you.”
- Natural English: “I don’t want anyone to interrupt you.”

In English, those usually feel the same, and in practice in Turkish these two often overlap in meaning.
But structurally:

In the first, you positively want the non-interruption.
In the second, you negatively want the interruption (you reject it).

Both are correct; Kimsenin seni bölmesini istemiyorum might be slightly more common in everyday speech, but your sentence is also perfectly natural Turkish.

Could we just say Kimse seni bölmesin instead of this whole bölmemesini istiyorum structure?

Yes, but the tone and structure change.

Kimse seni bölmesin.
- bölmesin is in the -sın / -sin negative imperative / optative form.
- This is like giving a wish / command / instruction:
  “Let nobody interrupt you.” / “No one should interrupt you.”
Kimsenin seni bölmemesini istiyorum.
- Uses a nominalized verb clause (“nobody interrupting you”) as the object of “istiyorum”.
- This explicitly frames it as what I want:
  “I want nobody to interrupt you.”

Both are correct and natural. The nominalized version (bölmemesini istiyorum) is more like stating your desire; the -mesin form feels more like a wish or soft command.

Is this a kind of subordinate clause? How does …mesini istiyorum work in general?

Yes. Turkish often uses nominalized verb forms instead of subordinate clauses with words like “that” in English.

Structure in your sentence:

Main verb: istiyorum – I want
Object (what I want): kimsenin seni bölmemesini – the fact that nobody interrupts you

General pattern:

[Subject in genitive] + [verb + -me/-ma + person ending] + (case)

Examples:

Senin erken gelmeni istiyorum.
- I want you to come early.
- literally: “I want your coming early.”
Onun sigara içmemesini rica ediyorum.
- I politely ask that he/she not smoke.
- literally: “I am requesting his/her not smoking.”
Çocukların sessiz olmasını bekliyorum.
- I expect the children to be quiet.
- literally: “I expect the children’s being quiet.”

So kimsenin seni bölmemesini istiyorum follows the same pattern:
“I want nobody’s interrupting you.”

Why can kimse appear with a negative verb without being a “double negative”? Here we have kimsenin and bölmemesi both with negation.

In Turkish, negative pronouns like kimse and hiç kimse normally require a negative verb; this is not treated as a “double negative” in the English sense.

Examples:

Kimse gelmedi. – Nobody came.
Hiç kimse bir şey söylemedi. – Nobody said anything.
Kimseyi görmedim. – I didn’t see anyone.

Your sentence:

kimsenin – “of nobody”
bölmemesi – “not interrupting”

Together they simply mean: “nobody interrupting”, not “nobody not interrupting” in a logical double-negative sense. It’s just how Turkish forms negative indefinite expressions.

So:

kimsenin seni bölmemesini istiyorum
is naturally understood as
“I want nobody to interrupt you.”

Can we change the word order? For example, is Kimsenin seni sen konuşurken bölmemesini istiyorum also correct?

Yes, Turkish word order is flexible, and you can move parts around for emphasis, as long as you keep the connections clear.

All of these are grammatical:

Sen konuşurken kimsenin seni bölmemesini istiyorum.
– Neutral: “While you are speaking, I want nobody to interrupt you.”
Kimsenin seni sen konuşurken bölmemesini istiyorum.
– Emphasis slightly shifts to “when you are speaking” inside the “nobody interrupting you” phrase.
Kimsenin sen konuşurken seni bölmemesini istiyorum.
– Both sen konuşurken and seni are very close to bölmemesini; still correct.

What you normally don’t change is:

kimsenin must stay attached to its verb phrase as its subject/possessor.
bölmemesini should stay as a unit, since it is the object of istiyorum.

So you can shuffle adjuncts like sen konuşurken, but kimsenin and bölmemesini should stay logically together.