"No, you do not see that dog."
Translation:Ne, ty toho psa nevidíš.
Isn't the personal pronoun rather out of place there? I would expect it if the English sentence was “No, you do not see that dog”, but there is no emphasis on the ‘you’.
As discussed above your question, the English sentence can also be "Ne, nevidíš toho psa" and "Ne, toho psa nevidíš." The "ty" is not required, and both of those alternatives are among the accepted translations.
How can say it is not “No, you do not see that dog”? I certainly can't exclude it and therefore translating it as such is completely legal and is done very frequently in this course.