YOU SAID:
I went to the park to play my favorite sport and I saw a animal running around.
INTO JAPANESE
好きなスポーツをするために公園に行ったら、動物が走り回っているのが見えた。
BACK INTO ENGLISH
When I went to the park to play my favorite sport, I saw animals running around.
INTO JAPANESE
好きなスポーツをするために公園に行ったとき、動物が走り回るのを見ました。
BACK INTO ENGLISH
When I went to the park to play my favorite sport, I saw animals running around.
That didn't even make that much sense in English.