"We were writing letters all day."

Translation: Celý den jsme psali dopisy.

[Laszlo.Sz]

Is “Jsme psali dopisy celý den” not acceptable?

[kacenka9]

No. When you omit the MY, the word order switches to PSALI JSME...

[Laszlo.Sz]

OK, thanks. Are you planning to write grammatical notes and summaries for the more advanced lessons as well in the future? It would be very useful.

[tragram]

Tips & Notes are in the process of being written, don't worry. :) In the meantime, you can Czech the grammar books someone posted here in the forum. ;)

[JakubCajthaml]

Dobrý den.
As I make my way through these exercises the third and fourth (and fifth) time, I experiment with word order, trying to infer rules. In this case, Celý den jsme dopisy psali didn't work. Is there a verb-object rule to be inferred? Why can't dopisy psali be used here?

[VladaFu]

That is really awkward. It stresses psali but in a way that I can only imagine it in meanings that would be better expressed differently.

But, as a first step, if you propose some non-SVO word order you should do that with some specific intention. You should have some idea what are you trying to say because such word orders change the meaning. If you just want to inform that we were writing letters all day, stay with the SVO order. If you want to stress something, you should also tell us what is that and we can recommend the best word order and intonation.