YOU SAID:

i was walking in the park while i tripped

INTO JAPANESE

つまずいた間、私は公園を歩いていました

BACK INTO ENGLISH

I was walking in the park while I stumbled

INTO JAPANESE

公園を歩いていてつまずきました

BACK INTO ENGLISH

I was walking in the park and stumbled.

INTO JAPANESE

公園を歩いていてつまずいてしまいました。

BACK INTO ENGLISH

I was walking in the park and tripped.

INTO JAPANESE

公園を歩いていてつまずいてしまいました。

BACK INTO ENGLISH

I was walking in the park and tripped.