Bu sinir kola gidiyor.

Because Turkish normally puts the verb last in a neutral sentence.

So the structure here is:

• Bu sinir = subject
• kola = destination / direction
• gidiyor = verb

A very natural Turkish pattern is:

• Subject + place/direction + verb

That is why Bu sinir kola gidiyor sounds normal.

Bu means this.

So bu sinir means this nerve.

A few useful points:

• bu comes before the noun
• it does not change for gender
• it does not need extra agreement endings here

Compare:

• bu sinir = this nerve
• bu kol = this arm

Because kol has the dative ending here.

• kol = arm
• kol-a = to the arm

The dative case is often used for:

• movement to a place
• direction toward something
• a target or endpoint

Since the verb is gitmek (to go), Turkish marks the destination with the dative:

• eve gidiyor = goes home / goes to the house
• okula gidiyor = goes to school
• kola gidiyor = goes to the arm

Because of vowel harmony.

The dative ending has two forms:

• -a
• -e

Which one you use depends on the last vowel of the noun.

In kol, the last vowel is o, which is a back vowel, so the ending becomes -a:

• kol + a = kola

More examples:

• ev → eve
• okul → okula
• şehir → şehre

So kola follows normal vowel harmony.

Gidiyor is the present continuous form of gitmek (to go).

It is made from the verb stem plus -iyor.

In many cases, this form corresponds to English is going. But in Turkish, it is also very commonly used in descriptions and explanations where English might use the simple present.

So even if the English meaning is something like goes to the arm, Turkish can still naturally use gidiyor.

Both can be possible in different contexts, but they do not feel exactly the same.

• gidiyor often sounds like a descriptive, immediate, explanatory statement
• gider is more general, habitual, or timeless

In anatomy or when pointing something out on a diagram, gidiyor is very natural, like saying:

• This nerve goes to the arm
• This vein goes to the heart

So even though English often uses the simple present for facts, Turkish frequently uses -iyor in this kind of explanation.

Good question. The dictionary form is gitmek, but in some conjugations the stem appears as gid-.

So:

• dictionary form: gitmek
• present continuous: gidiyor

This is a common stem change in this verb. You should learn it as part of the verb’s normal conjugation.

Some useful forms:

• gidiyor = is going / goes
• gidecek = will go
• gider = goes / would go
• gitti = went

So gitmek is the infinitive, but not every form keeps git- exactly.

Because kola is marked with the dative ending, so it is clearly a destination, not the subject.

That leaves bu sinir as the subject.

Turkish often shows grammatical roles through case endings, not just word order. Here:

• bu sinir = unmarked noun phrase, so it works as the subject
• kola = marked direction to the arm
• gidiyor = the action

So the sentence is understood as:

• This nerve → goes → to the arm

Turkish does not use articles the same way English does.

There is no direct everyday equivalent of the in this sentence.

Also, Turkish does not need an a/an here either.

Instead, Turkish often relies on:

• context
• word order
• demonstratives like bu (this)
• the number bir, which can sometimes mean a/an

So bu sinir already clearly means this nerve, and no article is needed.

Yes, Turkish word order is somewhat flexible, but changing it usually changes the focus or emphasis.

The neutral order is:

• Bu sinir kola gidiyor.

If you move things around, the sentence may still be grammatical, but it may sound marked or emphasize a different part.

For a learner, the safest choice is to keep the neutral pattern:

• subject + direction/place + verb

So Bu sinir kola gidiyor is the best basic version to learn first.

A simple pronunciation guide is:

boo see-neer ko-la gee-dee-yor

A few notes:

• u in bu is like oo
• i in sinir and gidiyor is a clear ee sound
• every vowel is pronounced clearly
• r is lightly pronounced

So the rhythm is fairly even:

Bu si-nir ko-la gi-di-yor.

Turkish pronunciation is usually more regular than English spelling, which is good news for learners.