Learn Hardcore Turkish: Hizmetli, bulaşık makinesinin deterjan bölmesine deterjan koydu. - The maid put detergent into the dishwasher’s detergent compartment.

Turkish has no articles. Definiteness is shown by context or by suffixes:
• deterjan koydu = “(she) put (some) detergent” (indefinite)
• deterjanı koydu = “(she) put the detergent” (definite)
You can also add bir (“a”) for indefiniteness: bir deterjan koydu = “she put a detergent.”

What part of speech is hizmetli, and how is it functioning here?

Hizmetli is a noun meaning “attendant/maid/servant.” Here it’s the subject in the nominative case, so it has no suffix.

Why doesn’t deterjan take the accusative ending -ı in deterjan koydu?

The accusative suffix -(y)ı/-i/-u/-ü marks definite direct objects. Since deterjan is indefinite (some detergent) and a mass noun, it remains unmarked. If you meant “the detergent,” you would say deterjanı koydu.

Why is there a suffix -nin on bulaşık makinesinin?

That -nin is the genitive case marker showing possession: “of the dishwasher.” Turkish uses a genitive-possessive construction:
bulaşık makinesi (“dishwasher”) → add -nin → bulaşık makinesinin (“of the dishwasher”).

Can you break down bulaşık makinesinin into its morphological parts?

bulaşık (“dish(es)”)
makine (“machine”)
-si (3rd-person possessive → “its,” forming bulaşık makinesi = “dishwasher”)
-nin (genitive → “of the,” giving bulaşık makinesinin = “of the dishwasher”)

What do the suffixes -si and -ne in bölmesine mean?

Start with bölme = “compartment.”
-si = third-person possessive (“its compartment”), because the compartment belongs to something.
-ne = dative case (“to”), so bölmesi + ne → bölmesine = “to its compartment.”

Why is the dative ending -ne here instead of a locative -de?

-ne (from -e) is the dative marker, showing movement or direction into/to.
-de would be locative (“in/on/at”), which would mean “in the compartment” rather than “into the compartment.”

Why is there a comma after Hizmetli? Is it required?

The comma is optional. Writers sometimes insert it to pause for clarity or emphasis on the subject. In everyday prose you can drop it:
Hizmetli bulaşık makinesinin deterjan bölmesine deterjan koydu.

How is the past tense of koymak formed as koydu?

Take the stem koy- (“to put”) + past-tense suffix -du (vowel-harmonized) = koydu (“he/she/it put”). In general, Turkish past tense is formed with -(y)dı/-di/-du/-dü after consonant-ending stems.

Why does the word deterjan appear twice in the sentence?

The first deterjan is part of the compound noun deterjan bölmesi (“detergent compartment”). The second deterjan is the actual detergent being placed into that compartment.