YOU SAID:

i killed a man and hid the body

INTO JAPANESE

私は人を殺して死体を隠した

BACK INTO ENGLISH

I killed someone and hid the corpse.

INTO JAPANESE

人を殺して死体を隠した。

BACK INTO ENGLISH

He killed someone and hid the body.

INTO JAPANESE

彼は人を殺して死体を隠した。

BACK INTO ENGLISH

He killed people and hid the bodies.

INTO JAPANESE

彼は人を殺し、死体を隠した。

BACK INTO ENGLISH

He killed people and hid the bodies.