Questions & Answers about To był okropny dzień.
In this sentence, to is a very common Polish word used in statements like This was..., That was..., or It was....
So To był okropny dzień is a natural way to say That/It was a terrible day.
A few useful points:
- to here does not behave exactly like English this
- it often introduces identification or description
- it is extremely common in sentences like:
If you used ten, that would be more like this specific one and would not sound as natural in this sentence.