Ben destinasyonu değiştirdiğimde rota da yeniden belirlendi.

When I changed the destination, the route was also redefined.

Breakdown of Ben destinasyonu değiştirdiğimde rota da yeniden belirlendi.

• ben: I
• da: also
• yeniden: again
• değiştirmek: to change
• -ince: when
• -ı: accusative
• destinasyon: the destination
• rota: the route
• belirlenmek: to be determined

Questions & Answers about Ben destinasyonu değiştirdiğimde rota da yeniden belirlendi.

Why is there a -u at the end of destinasyonu?

The -u is the accusative suffix, marking destinasyon as a definite direct object (“the destination”). In Turkish, when you talk about a specific object, you add -ı/-i/-u/-ü according to vowel harmony. Here destinasy-on + ‑u → destinasyonu (“the destination”).

How is değiştirdiğimde built, and what does each part do?

değiştir-di-ğ-im-de breaks down as:

• değiştir: verb stem “change”
• -di: past tense marker (“changed”)
• -ğ: buffer consonant to avoid two vowels in a row
• -im: 1st person possessive (“my change,” i.e. “that I changed”)
• -de: temporal locative meaning “when.”
  Put together, değiştirdiğimde = “when I changed.”

In rota da, is da the locative case or something else?

Here da is the conjunction “also/too,” not the locative case. Written as a separate word, rota da means “the route too” or “the route as well.”

How can I tell the difference between the locative -da/de and the conjunction da?

• The locative suffix attaches directly to the noun (no space): rotada = “at/on the route.”
• The conjunction “also/too” is separate: rota da = “route too.”
  Always watch for the space: suffix = case, separate = “also.”

What is yeniden, and can I use tekrar instead?

yeniden is an adverb meaning “again” or “anew.” You can often swap in tekrar (“again”) with no major change:
“rota da yeniden belirlendi” → “rota da tekrar belirlendi.” Both are common.

Why is belirlendi in passive voice, and how is that formed?

belirlendi = “it was determined.” To form passive:

1. Start with belirle-mek (“to determine”).
2. Insert passive -n-: belirle + n + mek → belirlenmek (“to be determined”).
3. Add past tense -di: belirlendi (“it was determined”).

Could I rewrite the sentence in active voice? If so, how?

Yes. Active would require an agent. For example:
“Ben destinasyonu değiştirdiğimde rota da yeniden ben belirledim.”
= “When I changed the destination, I re-determined the route.”

Can I use değiştirince instead of değiştirdiğimde, and what’s the nuance?

Yes: destinasyon değiştirince rota da yeniden belirlendi also means “when the destination is/was changed, the route was re-determined.”

• değiştirince attaches -ince directly to the verb root, giving a general “when X happens.”
• değiştirdiğimde specifies “when I changed” by including the 1st-person possessive.

Do I need a comma after değiştirdiğimde?

Commas before subordinate clauses are optional in Turkish. You can write either

• Ben destinasyonu değiştirdiğimde rota da yeniden belirlendi.
• Ben destinasyonu değiştirdiğimde, rota da yeniden belirlendi.
  Both are acceptable; the comma is a matter of style.

Is ben necessary at the start of the sentence?

No. Turkish verbs encode person, so pronouns are usually dropped unless you want emphasis.
Destinasyonu değiştirdiğimde rota da yeniden belirlendi. is perfectly natural.