YOU SAID:

i throw my father's hat down the stairs

INTO JAPANESE

私は階段を降りて父の帽子を投げる

BACK INTO ENGLISH

I descended the stairs, throwing his hat

INTO JAPANESE

私は階段を降りて、彼の帽子を投げて

BACK INTO ENGLISH

I descended the stairs, threw his hat

INTO JAPANESE

私は階段を降りて、彼の帽子を投げた

BACK INTO ENGLISH

I descended the stairs, threw his hat