YOU SAID:

is was walking down the road when i saw a donkey

INTO JAPANESE

道を歩いていたらロバを見た

BACK INTO ENGLISH

I saw a donkey as I was walking down the street.

INTO JAPANESE

道を歩いているとロバを見かけました。

BACK INTO ENGLISH

I saw a donkey while walking on the road.

INTO JAPANESE

道を歩いているとロバを見かけました。

BACK INTO ENGLISH

I saw a donkey while walking on the road.