Learn Hardcore Turkish: Ameliyat öncesi antibiyotik almayı unutmayın. - Don’t forget to take your antibiotic before the surgery.

ameliyat = surgery
önce = before
Add the possessive suffix -si to önce → öncesi = its before, so ameliyat öncesi = before surgery or preoperative. As a fixed time expression it doesn’t need an extra case ending (just like toplantı sonrası for after the meeting).

Can I use ameliyattan önce instead of ameliyat öncesi, and is there any difference?

Yes—both mean before surgery.
• ameliyattan önce = ameliyat + ablative -tan + önce, literally from the surgery before.
• ameliyat öncesi is a single nominal phrase (more concise/formal), whereas ameliyattan önce is more analytical.

Why is almak turned into almayı in this sentence?

Turkish verbs become noun-phrases with -mAk (infinitive) or -mA (gerund). When unutmak (to forget) takes a verb as its object, you use the gerund -mA plus the accusative -yI:
root al- + -mA + -yI → almayı = (the act of) taking.
So antibiyotik almayı unutmayın literally is Don’t forget (the act of) taking the antibiotic = Don’t forget to take the antibiotic.

Why doesn’t antibiyotik have an article (a/an/the) or an accusative suffix like -i?

Turkish has no words for a or the. Definiteness is marked by the accusative case: direct objects take -ı/-i/-u/-ü only if they’re specific. Here it’s a generic instruction, so antibiyotik remains bare (indefinite)—you understand an antibiotic. If you meant a particular antibiotic, you could say antibiyotiği almayı unutmayın.

What do the parts unutmayın mean, and what do the suffixes -ma and -yın indicate?

• unut- = forget (root)
• -ma = negative suffix → do not forget
• -yın = 2nd-person plural (or polite singular) imperative ending
Together unut-ma-yın = do not forget (polite/respectful “you”).

How would I make this sentence more informal or more polite?

Informal singular (friend/family): drop the plural/polite ending → unutma
• Ameliyat öncesi antibiyotik almayı unutma.

More formal/polite: use -mayınız or add lütfen
• Ameliyat öncesi antibiyotik almayı unutmayınız.
• Lütfen ameliyat öncesi antibiyotik almayı unutmayınız.

Why is the verb at the end of the sentence, and can word order change in Turkish?

Turkish is an SOV language (Subject-Object-Verb), so the verb normally comes last. Other parts (subjects, objects, adverbials) can move around for emphasis, but the verb stays at the end in main clauses. E.g., Antibiyotik almayı ameliyat öncesi unutmayın is possible but less natural.

Can I add lütfen to soften the instruction, and where does it go?

Yes. lütfen (“please”) is flexible but usually placed at the beginning or just before the verb:
• Lütfen ameliyat öncesi antibiyotik almayı unutmayın.
• Ameliyat öncesi antibiyotik almayı unutmayın, lütfen.