Eğitim takvimi ön değerlendirmeden sonra hazırlandı.

Because eğitim takvimi is a noun compound in Turkish.

• eğitim = education, training
• takvim = calendar
• eğitim takvimi = the education/training calendar, training schedule

In this kind of compound, the second noun usually takes the 3rd person possessive ending:

• takvim → takvimi

So eğitim takvimi does not literally mean the calendar of the education in a full possessive sense; it is just the normal Turkish way to form a compound like:

• ders programı = course schedule
• şehir merkezi = city center
• yaz tatili = summer holiday

This is one of the most common things English speakers need to get used to in Turkish.

It is a compound noun meaning something like:

• training schedule
• education schedule
• training calendar

Which English translation sounds best depends on context. In Turkish, takvim is literally calendar, but in practical use it can refer to a planned schedule or timeline as well.

ön değerlendirmeden sonra means after the preliminary evaluation/assessment.

Breakdown:

• ön = pre-, preliminary, prior
• değerlendirme = evaluation, assessment
• değerlendirmeden = from the evaluation / after the evaluation
• sonra = after

The ending -den is the ablative case. After sonra, Turkish commonly uses a noun in the ablative:

• dersten sonra = after the lesson
• yemekten sonra = after the meal
• toplantıdan sonra = after the meeting

So:

• ön değerlendirmeden sonra = after the preliminary evaluation

Here it is written as two words, and that is normal.

• ön often functions like pre- or preliminary
• değerlendirme = evaluation

So ön değerlendirme = preliminary evaluation / initial assessment

Turkish sometimes forms concepts with separate words where English might prefer a prefix.

hazırlandı means was prepared.

It comes from the verb:

• hazırlamak = to prepare

The form hazırlanmak can mean to be prepared or sometimes to get ready, depending on context. Here it is passive-like:

• hazırlandı = was prepared

Breakdown:

• hazırlan- = be prepared / get prepared
• -dı = past tense

So the full sentence means that the schedule was prepared after the preliminary evaluation.

Yes, in this sentence it is understood as a passive-style form: was prepared.

Compare:

• Yetkililer eğitim takvimini hazırladı. = The officials prepared the training schedule.
• Eğitim takvimi hazırlandı. = The training schedule was prepared.

Turkish often uses this kind of form where English uses a passive.

Because Turkish normally prefers verb-final word order.

This sentence is structured like:

• Eğitim takvimi = subject
• ön değerlendirmeden sonra = time/post-event expression
• hazırlandı = verb

So the basic pattern is very natural in Turkish.

English often places elements more flexibly, but Turkish commonly saves the main verb for the end.

Yes. That is also natural.

Both are grammatical:

• Eğitim takvimi ön değerlendirmeden sonra hazırlandı.
• Ön değerlendirmeden sonra eğitim takvimi hazırlandı.

The difference is mainly focus or emphasis.

• Starting with Eğitim takvimi puts the schedule first.
• Starting with Ön değerlendirmeden sonra emphasizes the timing or sequence.

Turkish word order is flexible, but the verb usually stays near the end.

Because Turkish does not have definite articles like English the.

Whether something is understood as a or the usually depends on context.

So eğitim takvimi can mean:

• a training schedule
• the training schedule

In this sentence, it will usually be understood as the training schedule because the context probably makes it specific.

Because eğitim takvimi is the subject of the sentence, not the object.

In Turkish, the subject is usually in the basic form.

Compare:

• Eğitim takvimi hazırlandı. = The training schedule was prepared.
  Here eğitim takvimi is the subject.

• Yetkililer eğitim takvimini hazırladı. = The officials prepared the training schedule.
  Here eğitim takvimini is the direct object, so it takes the accusative ending -ni.

That contrast is very useful for learners.

It is the simple past tense.

• hazırlandı = was prepared / got prepared

The ending -dı / -di / -du / -dü (with vowel harmony and consonant changes) is one of the main Turkish past tense markers.

Examples:

• geldi = came
• başladı = started
• hazırlandı = was prepared

Very often, yes.

A very common pattern is:

• noun + -den/-dan + sonra

Examples:

• işten sonra = after work
• okuldan sonra = after school
• sınavdan sonra = after the exam

So değerlendirmeden sonra follows a very common rule.

Yes, it sounds fairly neutral to formal, especially because of words like:

• eğitim takvimi
• ön değerlendirme

These are common in administrative, academic, professional, or institutional contexts.

In everyday speech, people might still say it, but it sounds especially natural in reports, announcements, or official communication.