DuoLingo please, please, please!! Hire people who can correctly translate to English as well. And the Korean phrases are not awkward and not very helpful!! I can't think of a tie in my life where I ever had to tell someone that I do not throw bowls!Correct grammatical translation in English would be: I do not throw bowls or I did not throw a bowl.
Those involve different grammatical concepts. These sentences aren't made to be useful in daily life, they're to teach grammatical concepts. Your first sentence should be correct, but the second one is past tense, which hasn't been taught up to this point in the course.