YOU SAID:

please tell me you didn't steal the neighbour's cat

INTO JAPANESE

隣人の猫を盗まなかったって言って下さい

BACK INTO ENGLISH

Tell me you didn't steal your neighbor's cat.

INTO JAPANESE

隣人の猫を盗んでいないと言って下さい。

BACK INTO ENGLISH

Tell him you haven't stolen your neighbor's cat.

INTO JAPANESE

隣人の猫を盗んでいないと彼に言いなさい。

BACK INTO ENGLISH

Tell him you haven't stolen your neighbor's cat.