Learn Hardcore Turkish: Bulaşık deterjanı bitti, yenisini alacağım. - The dishwashing detergent is finished; I will buy a new one.

It’s the past tense of bitmek “to end/finish/run out.” With inanimate things, it usually means “it ran out/there’s none left.” So Bulaşık deterjanı bitti = “The dish soap ran out.”

Why is it deterjanı and not just deterjan?

This is a Turkish noun–noun compound (belirtisiz isim tamlaması): modifier + head with a 3rd person possessive suffix.

bulaşık (dishes) + deterjan-ı (detergent-3sg.poss) → “dishwashing detergent.”
The suffix here doesn’t mark ownership; it’s part of the compound pattern.

Is the -ı on deterjanı accusative case?

No. Here it’s the 3rd person possessive suffix of the compound, not the accusative. The whole subject is Bulaşık deterjanı, and the verb is bitti.

Could I say “Bulaşık deterjan bitti”?

No, that’s ungrammatical/nonnative. In such compounds, the head noun needs the possessive: bulaşık deterjanı.

How is bitti formed and pronounced?

Morphology: bit- (root) + -di (past) → due to consonant harmony it becomes -ti, yielding bitti (with a doubled t).
Pronunciation: roughly “bit-TEE.”

What’s the difference between bitti, kalmadı, and tükendi?

bitti: “(it) finished/ran out” (common, everyday).
kalmadı: “none left” (focus on zero remaining).
tükendi: “sold out/depleted” (more formal or for stock).

What does yenisini consist of?

yeni (new) + -si (3sg possessive → “the new one [of it]”) + buffer -n-
- -i (accusative).
  So yenisini = “the new one” as a direct object.

Does Yenisini alacağım mean “the new one” (definite) or “a new one” (indefinite)?

Morphologically it’s definite (“the new one”), so it takes accusative. In everyday speech it often corresponds to English “a new one.” If you want clearly indefinite, say Yeni bir tane alacağım or Yeni bir deterjan alacağım.

Why is there a buffer -n- in yenisini?

Turkish avoids vowel-vowel clashes between suffixes. yeni-si ends in a vowel; adding accusative -i requires the buffer -n-: yeni-si-n-i.

Is alacağım a future tense? How is it pronounced?

Yes: al- (take/buy) + -acak (future) + -ım (1sg) → alacağım “I will buy.” The letter ğ lengthens the preceding vowel; it’s not a hard “g.” Roughly “a-la-jaa-m.”

Could I use alırım instead of alacağım?

Alacağım: planned/decided future (“I’m going to buy”).
Alırım: generic/habitual or on-the-spot promise (“I’ll buy, sure”). Both can fit, but alacağım sounds like a concrete plan.

Can I say Bulaşık deterjanı kalmadı, yenisini alacağım?

Yes. It’s equally natural: “There’s no dish soap left; I’ll buy a new one.”

Is the comma necessary? Could I use ve?

A comma between two short independent clauses is common in Turkish. You could also say Bulaşık deterjanı bitti ve yenisini alacağım. Both are fine.

How would I say “We ran out of dish soap; we’ll buy a new one”?

Bulaşık deterjanımız bitti, yenisini alacağız.
The -ımız marks “our detergent.”

What’s the difference between bitmek and bitirmek?

bitmek: intransitive “to end/run out” (Detergent ran out: deterjan bitti).
bitirmek: transitive “to finish [something]” (We finished the detergent: deterjanı bitirdik).

Could I say Bulaşık sabunu bitti for “dish soap”?

People usually say bulaşık deterjanı for the liquid used in dishwashing. Bulaşık sabunu would be understood but sounds like a bar/solid soap.

Why is it deterjanı with -ı and not -i?

Vowel harmony: the last vowel in deterjan is a (a back vowel), so the possessive suffix uses the back form -ı.

Is there a more “discovered result” way to say it?

Yes: Bulaşık deterjanı bitmiş, yenisini alacağım. The -miş perfect suggests you’ve just found out or are reporting evidence (“looks like it’s run out”).