Questions & Answers about Fuar alanında stand kuruluyor.
Because fuar alanı (“fairground”) is a compound where alan (“field/area”) belongs to fuar (“fair”), so you first add the 3rd-person possessive -ı to get alanı (“its field” = “fairground”) and then the locative -nda (“in/at”).
Formation:
• alan + -ı → alanı
• alanı + -nda → alanında (“in/at the fairground”)
If you just had alan by itself, you would get alanda for “in the field/area.”
Turkish applies case endings after possessive endings when a noun is part of a compound.
1) alan + -ı (3rd-person possessive, because it’s the “fair’s field”) → alanı
2) alanı + -nda (locative) → alanında
The order is always root → possessive → case.