Learn Hardcore Turkish: Konaklama rezervasyonunu yaptıktan sonra şehir turuna katıldık. - After making the accommodation reservation, we joined the city tour.

konaklama comes from the verb konaklamak (“to stay, lodge”) and means “accommodation” or “lodging.”
rezervasyon is the loanword for “reservation.”
Together, konaklama rezervasyonu literally means “accommodation reservation,” i.e. the booking you make for a place to stay.

Why does rezervasyonunu end with -unu? Is this a possessive form?

No, it isn’t marking possession here but the accusative (definite object) case.
• The direct-object suffix in Turkish follows vowel harmony: -ı/-i/-u/-ü.
• Speakers often insert a buffer consonant n before it to ease pronunciation, especially with loanwords.
So rezervasyon + buffer n + accusative u → rezervasyonunu, meaning “the reservation” as a definite object of yapmak.

How is yaptıktan sonra formed? What are the roles of -tıktan and sonra?

This is a standard pattern for “after doing something.” Break-down:

yap- – verb root “to do.”
-tık – verbal noun/participle suffix, turning “do” into “the act of doing.”
-tan – ablative case on that verbal noun, literally “from the act of doing.”
⇒ yaptıktan = “after having done.”
sonra = “after.”
Put together: yaptıktan sonra = “after having done (it).”

What is the difference between yaptıktan sonra and using yapınca (“when/once you do”)?

Both link two actions, but:

yapınca (converb -ınca/ünce) often means “when” or “as soon as,” and can stress immediacy or cause–effect.
yaptıktan sonra strictly means “after having completed” the first action, with no implication of immediate result beyond sequence.
Example:
• Kapıyı kapatınca ışık otomatik sönüyor. (“When/once you close the door, the light automatically goes off.”)
• Kapıyı kapattıktan sonra ışık sönüyor. (“After you have closed the door, the light goes off.”)

Why can’t we just say yaptık sonra or use a simple conjunction to express “after we made it”?

In Turkish, you need the verbal noun + ablative + sonra construction to mean “after doing X.” You can’t attach sonra directly to a finite-past verb.
Incorrect: “Rezervasyonu yaptık sonra …”
Correct: “Rezervasyonu yaptıktan sonra …”

Why is şehir turuna in the -a form (dative), not the accusative?

The verb katılmak (“to join/participate”) takes its object in the dative case: you join to something.
Thus şehir turu (“city tour”) → şehir turu-na → şehir turuna katıldık = “we joined the city tour.”

How do we break down katıldık into root and suffixes?

• katıl- = verb root “to join/participate.”
• -dı = past-tense suffix (vowel-harmonized).
• -k = 1st-person-plural ending (“we”).
Put together: katıl-dı-k → katıldık = “we joined/participated.”

There is no biz in the sentence. How do we know the subject is “we”?

Turkish commonly omits subject pronouns because the verb ending already indicates person and number. Here -dık in katıldık tells you the subject is we (1st person plural).

Could we swap the two clauses? For example: Şehir turuna katıldıktan sonra konaklama rezervasyonunu yaptık.

Grammatically you can place either clause first, but the order of events stays tied to the temporal marker.
• Konaklama rezervasyonunu yaptıktan sonra şehir turuna katıldık. = “After making the reservation, we joined the tour.”
• Şehir turuna katıldıktan sonra konaklama rezervasyonunu yaptık. = “After joining the tour, we made the reservation.”
In both, -dıktan sonra fixes which action comes first.

Can we use yapıp instead of yaptıktan sonra?

Yes. The converb -ıp/ıp gives a casual sense of sequence:
Konaklama rezervasyonunu yapıp şehir turuna katıldık.
= “We made the reservation and then joined the city tour.”
The nuance is slightly looser—-ıp simply strings actions together—whereas yaptıktan sonra emphasizes “only once X was completed, we did Y.”