YOU SAID:
I went to the bathroom on Monday.
INTO JAPANESE
私は月曜日にトイレに行った。
BACK INTO ENGLISH
I went to the toilet on Monday.
INTO JAPANESE
月曜日に、トイレに行きました。
BACK INTO ENGLISH
On Monday, went to the bathroom.
INTO JAPANESE
月曜日に、トイレに行きました。
BACK INTO ENGLISH
On Monday, went to the bathroom.
That didn't even make that much sense in English.