"Because I am not good at swimming, I practice a lot."
Would it have been okay to use へた だ から rather than へた です から in this sentence?
So since we do not know a thing about the context, both versions should be alright.
泳ぐのがじょうずではないので？？？ Isn't that more correct? I feel like that matters. In English, saying "I'm bad at" has a different feel than "I'm not good at" ......no? Idk maybe I'm just splitting hairs.
I agree that that's more accurate, and I think your answer should be accepted. Japanese and English are just so incompatible that it's hard to have one "right" answer.
There is no difference between using のが or こと, same difference. こと is more natural, のが isn't used as often in normal language.
I wrote the answer exactly as given, albeit with kanji instead of およぐ (as only the kanji was a choice) and got it WRONG!
Why the 'no'? If the sentence was 'Watashi wa oyogu ga heta desu', there also wouldn't be a 'no'.
“Oyogu” is a verb (to swim). In order to make it into a noun (swimming) you have to add “no” at the end. If you wanted to say “I’m not good at swimming “, it would be 泳ぐのが下手です (oyogu no ga heta desu).
No, it's not possible to put を after a verb like that. You usually add する to make a noun into a verb, so there's no need to do so with a verb. You can say 水泳をするのが (suiei o suru no ga), where 水泳 (suiei) is a noun meaning "swimming", but I don't think native speakers would normally say it that way.