Learn Hardcore Turkish: Sözleşmede son tarih açıkça yazıyor, son tarihi geçirmemeliyiz. - The deadline is written clearly in the contract; we must not miss the deadline.

sözleşme = contract
-de = locative suffix “in/on/at,” chosen by vowel harmony (last vowel is front, so -de not -da). Also note consonant harmony: after a voiceless consonant you get -ta/te (e.g., kitapta “in the book”), but after a vowel or voiced consonant you get -da/de (e.g., evde, şehirde).

Who is the subject of yazıyor? Where is the Turkish equivalent of “it” in “it says”?

Turkish doesn’t need a dummy “it.” yazıyor here is used impersonally to mean “it says”/“it is written.” The clause Sözleşmede … yazıyor is understood as “In the contract, it says …” without an explicit subject.

Why is it son tarih in the first clause but son tarihi in the second?

In the first clause, son tarih (“the deadline”) is just the content of what “it says,” so no object marking is needed.
In the second clause, son tarihi is a definite direct object of the verb (we must not pass/miss it), so it takes the accusative -i.

Can I say son tarihi geçmemeliyiz instead of son tarihi geçirmemeliyiz? What’s the difference?

Yes. Both are heard:

geçmek = to go past/exceed. Son tarihi geçmemeliyiz is straightforward: “We must not go past the deadline.”
geçirmek (causative) often means “to make/pass (something), to spend (time).” With deadlines, you’ll hear son tarihi geçirmemeliyiz in everyday speech (“we mustn’t let the deadline pass”), though many prefer geçmek or kaçırmak for clarity.

Is kaçırmak also possible for “miss a deadline”?

Absolutely. Son tarihi kaçırmamalıyız = “We must not miss the deadline.” This is very common in business/academic contexts. Another formal option is son tarihi aşmamalıyız (“we must not exceed the deadline”) or more specific son teslim tarihini (deadline for submission) kaçırmamalıyız/aşmamalıyız.

What is the morphology of geçirmemeliyiz?

geç- = pass
-ir- = causative (“make/pass something”)
-me- = negation
-meli = necessity/obligation (“should/must”)
-yiz = 1st person plural “we” (the buffer y is for pronunciation) Overall: “we should/must not cause [it] to pass” → “we must not go past it.”

Why use açıkça and not just açık? What does açıkça add?

açıkça is an adverb meaning “clearly/explicitly,” formed with the adverbial suffix -CA from açık (“clear”). It modifies the manner of “being written.” Alternatives: net bir şekilde, açık açık (more colloquial), bariz bir şekilde.

Is yazıyor the best choice? How do yazılı, yazılmış, belirtiliyor, or yer alıyor differ?

yazıyor: informal, natural “it says.”
yazılı: “written/stated” (adjectival, more formal): Sözleşmede son tarih açıkça yazılı.
yazılmış: “has been written” (resultative passive): … açıkça yazılmış.
belirtiliyor/belirtilmiş: “is (being)/has been specified” (formal/legal tone).
yer alıyor: “is included/appears” (neutral formal). All convey the same idea with varying register.

Why is there a comma between the clauses? Could I use connectors like “therefore” or “because”?

Turkish often links two closely related independent clauses with a comma. You can also write:

Sözleşmede son tarih açıkça yazıyor; son tarihi geçirmemeliyiz.
Or add a connector: Sözleşmede son tarih açıkça yazıyor, bu yüzden son tarihi geçirmemeliyiz.
If you want “because,” flip the order: Son tarihi geçirmemeliyiz, çünkü sözleşmede son tarih açıkça yazıyor.

Is son tarih the normal way to say “deadline”? Any alternatives?

Yes, son tarih is common. Alternatives include:

son teslim tarihi (submission deadline)
başvuru son tarihi (application deadline)
bitiş tarihi (end date, sometimes used as deadline depending on context)
son gün (last day)

Could tarihi here mean “its date” or “historical”? How do I tell?

Written tarihi can be:

Accusative of tarih (“the date”): our case here, son tarihi = “the deadline” (as a definite object).
3rd-person possessed (“its date”): e.g., başvurunun son tarihi (“the application’s deadline”).
“Historical” (traditionally written tarihî with a circumflex, but often unmarked in modern writing): tarihi eser (“historical artifact”). Context disambiguates it.

Can I change the word order?

Yes, within limits. Turkish is flexible but tends to place the verb last.

Sözleşmede son tarih açıkça yazıyor. (neutral, sets the place first)
Son tarih sözleşmede açıkça yazıyor. (focus on “deadline”)
Son tarihi geçirmemeliyiz. (neutral SOV) You can front elements for emphasis: Biz son tarihi geçirmemeliyiz (emphasizing “we”).