"Yes, we see this dog."

Translation: Tak, widzimy tego psa.

[DarkAvenger86]

Why is "Tak, widzimy ten psa" not good? It says tego is the right word instead of ten.

[immery]

you need accusative after widzimy, pies is animated , and has Accusative=Genitive psa, so you use Accusative=Genitive tego

[83annalisa]

Can someone explain to me "accusative" and "genetive"

[Jellei]

It's a very wide topic, so I'd advise taking a look here and looking for posts about cases: https://www.duolingo.com/comment/16296174