YOU SAID:
I slept with your mom tonight
INTO JAPANESE
今夜はお母さんと寝た
BACK INTO ENGLISH
i slept with my mom tonight
INTO JAPANESE
今夜は母と寝ました
BACK INTO ENGLISH
I slept with my mother tonight
INTO JAPANESE
今夜は母と寝ました
BACK INTO ENGLISH
I slept with my mother tonight
That didn't even make that much sense in English.