Learn Hardcore Turkish: Koşuda madalya aldı; çalışkanlığı herkesin hoşuna gitti. - She got a medal in the run; everyone liked her hard work.

The semicolon links two closely related independent clauses. You could use a period instead with no real change in meaning. A comma by itself would be incorrect (it would create a comma splice). You could also use ve (and): Koşuda madalya aldı ve çalışkanlığı herkesin hoşuna gitti. The semicolon just keeps the two thoughts tightly connected without an explicit conjunction.

Whose diligence does çalışkanlığı refer to, and why does it end with -ı even though it’s the subject?

It means his/her diligence (the same person who got the medal). The ending -ı here is not accusative; it’s the 3rd‑person possessive suffix. Structure:

çalışkan (hardworking) + -lık (noun-maker) → çalışkanlık (diligence)
- -(s)ı (3SG possessive) → çalışkanlığı (his/her diligence)

As the subject of gitti, it stays in the nominative, so there is no accusative marking. Don’t confuse it with çalışkanlığını (3SG.POSS + ACC), which would be an object form and would be wrong here.

How does the construction X, Y’nin hoşuna gitmek work?

It literally means “X goes to Y’s liking,” i.e., “Y likes X.” Grammar:

X = the thing liked (subject of gitmek)
Y’nin = the person who likes it (genitive possessor)
hoşuna = hoş (pleasant) + -u (3SG.POSS) + -na (dative) → “to his/her liking”

Example: Film, Ali’nin hoşuna gitti. = “Ali liked the movie.” In the sentence, çalışkanlığı is X (subject), and herkesin supplies Y (the liker).

Why is it herkesin hoşuna gitti and not herkesin hoşlarına gitti?

Herkes is grammatically singular in Turkish, so the default is the 3rd‑singular possessive in hoşuna. You will hear hoşlarına with herkesin (treating “everyone” as plural) in speech, but the standard, neutral choice is herkesin hoşuna gitti.

Why is madalya not marked as madalyayı, even though it’s a direct object of aldı?

In Turkish, indefinite direct objects are unmarked. Madalya aldı = “(He/She) got a medal.” Use the accusative only for definite/specific objects: Madalyayı aldı = “(He/She) got the medal (that specific one).”

Can I add bir: Koşuda bir madalya aldı? Does it change the meaning?

Yes. Bir emphasizes the “one-ness” of the medal: “He/She got one medal.” Without bir, madalya is still indefinite (“a medal”), just a bit less emphatic about the number.

Is madalya aldı natural, or should it be madalya kazandı?

Both are natural. Madalya kazandı (“won a medal”) is more precise/formal for competitions. Madalya aldı (“got/received a medal”) is very common and idiomatic in sports news and everyday speech. Neither sounds wrong.

What exactly does koşuda mean? Why the locative -da? Could I say yarışta?

Koşuda = koşu (running/race event) + -da (locative) → “in/at the race (running event).” You could also say yarışta (“in the race”), which is equally natural. The locative -da/-de marks place/time (“at/in/during”). Alternatives would change meaning:

koşuya (dative) = “to the race”
koşuda (locative) = “in/at the race”
koşarken = “while running” (different structure/meaning)

Where is the subject pronoun? How do we know it’s he/she?

Turkish is pro‑drop. The subject o is omitted because the verb endings (-dı/-di in aldı/gitti) already show 3rd‑person singular. The possessed noun çalışkanlığı signals that the same person’s diligence is being referred to. Context ties both clauses to the same person.

Can I change the word order, like Herkesin hoşuna çalışkanlığı gitti or Madalya aldı koşuda?

Çalışkanlığı herkesin hoşuna gitti (original) is the most neutral. Herkesin hoşuna çalışkanlığı gitti is grammatical and puts extra focus on çalışkanlığı at the end.
Koşuda madalya aldı is the natural order (place/time early, verb late). Madalya aldı koşuda is possible but sounds marked/less natural in neutral contexts.

What is the morphology of çalışkanlığı? How do we get from çalışkan to çalışkanlığı?

çalışkan (adj. “hardworking”)
- -lık/-lik → çalışkanlık (noun “diligence/hardworkingness”)
- -(s)ı (3SG possessive) → çalışkanlığı (“his/her diligence”)

Note the consonant change: k → ğ before a vowel-initial suffix: çalışkanlık + ı → çalışkanlığı.

How is ğ pronounced in çalışkanlığı?

Ğ (yumuşak g) is not a hard “g.” It lengthens or glides the preceding vowel. In çalışkanlığı, you don’t pop a separate “g” sound; you smoothly connect the vowels, roughly: cha-lish-kahn-lɯ-ı (with a lengthened ı before the ğ).

Could I rephrase the second clause as Herkes onun çalışkanlığını beğendi? Is the meaning the same as hoşuna gitti?

Yes. Herkes onun çalışkanlığını beğendi = “Everyone liked his/her diligence.” It’s an active verb with the likers as the subject. Çalışkanlığı herkesin hoşuna gitti keeps the diligence as the subject and is slightly more impersonal. Both are fine; hoşuna gitmek is very idiomatic.

Why simple past aldı / gitti? What would alıyor / gidiyor or gitmiş mean?

aldı / gitti: completed past events (“got,” “pleased/was liked”).
alıyor / gidiyor: ongoing/habitual (“is getting,” “is pleasing/keeps pleasing”).
gitmiş: reported/inferential past (“apparently/it seems it pleased them” or “I heard they liked it”).

What does herkesin mark here? Is it genitive? Why not herkese or herkesi?

Herkesin is the genitive form of herkes and serves as the possessor for hoşu(na) in the fixed pattern X, Y’nin hoşuna gitmek. You don’t use herkese (dative) or herkesi (accusative) in this construction.