YOU SAID:

i once was walking and i saw 12 tiny purple ducks in 2 rows

INTO JAPANESE

私はかつて歩いていて、12 匹の小さな紫色のアヒルが 2 列に並んでいるのを見ました

BACK INTO ENGLISH

I was walking once and saw twelve little purple ducks standing in two rows

INTO JAPANESE

私は一度歩いていて、12羽の小さな紫のアヒルが2列に並んでいるのを見ました

BACK INTO ENGLISH

I was walking once and saw twelve little purple ducks standing in two rows