YOU SAID:

today i'm going to visit my uncle at the hospital because he had a terrible car accident

INTO JAPANESE

今日は彼がひどい自動車事故を起こしたので病院で私の叔父を訪ねるつもりです

BACK INTO ENGLISH

I am going to visit my uncle at the hospital because he had a bad car accident today

INTO JAPANESE

今日は彼が悪い車の事故に遭ったので病院で私の叔父を訪ねるつもりです

BACK INTO ENGLISH

I am going to visit my uncle at the hospital because he had a bad car accident today