Learn Hardcore Dutch: Vorige week schreef ik elke avond in mijn dagboek. - Last week I wrote in my diary every evening.

schreef is the simple past (preterite) form of the verb schrijven (“to write”). In English you’d say “wrote.” Dutch has two main ways to talk about past actions:

The simple past (like schreef), often used in narratives or written language.
The perfect (compound past), formed with hebben or zijn
- past participle (e.g. ik heb geschreven).

Why does the verb schreef come before ik in this sentence?

This is due to Dutch V2 word order. When you start a main clause with anything other than the subject (here vorige week, a time expression), the finite verb must occupy the second position. Structure:
1) Adverbial (Vorige week)
2) Finite verb (schreef)
3) Subject (ik)
4) Rest of the sentence

What are the infinitive and past participle forms of schreef?

Infinitive: schrijven (“to write”)
Past participle: geschreven

You’ll need geschreven when you form the perfect: “Ik heb elke avond in mijn dagboek geschreven.”

Why is it in mijn dagboek and not op mijn dagboek?

You use in because you are writing inside the pages of your diary (boek). op would suggest writing on top of something (e.g. “op het bord,” on the board). For books and notebooks the standard preposition is in.

What does elke avond mean and is it interchangeable with iedere avond?

elke avond means every evening. You can also say iedere avond – they are synonyms. Subtle nuance:

elke is slightly more colloquial.
iedere can sound a bit more formal or emphatic.

Could I reorder the sentence and say Ik schreef elke avond vorige week in mijn dagboek? Would that still be correct?

Yes. If you start with the subject (Ik), you follow the normal Subject-Verb-Object order, and no inversion is needed. Both are correct:

Vorige week schreef ik…
Ik schreef vorige week…

You can even shuffle elke avond and vorige week a bit, but watch for V2 rules if you front a time phrase.

When should I use the simple past versus the perfect in Dutch? Could I say Vorige week heb ik elke avond in mijn dagboek geschreven?

Yes, that’s perfectly fine. In spoken Dutch the perfect is very common for past actions:

Perfect: Vorige week heb ik elke avond in mijn dagboek geschreven.
Simple past: Vorige week schreef ik elke avond in mijn dagboek.
Use simple past more in storytelling or written narratives; the perfect is more colloquial.

Why is dagboek one word in Dutch, and what’s the closest English equivalent?

Dutch often forms compound nouns by joining words: dag (day) + boek (book) = dagboek. In English we write it as two words (“day book”) or more commonly as diary or journal.