YOU SAID:

i was playing with my ball

INTO JAPANESE

私は自分のボールで遊んでいました

BACK INTO ENGLISH

I was playing with my ball

INTO JAPANESE

ボールで遊んでいた

BACK INTO ENGLISH

I was playing with a ball

INTO JAPANESE

私はボールで遊んでいました

BACK INTO ENGLISH

I was playing with a ball