YOU SAID:
My mom has potatoes in the oven
INTO JAPANESE
母はオーブンにジャガイモを入れています
BACK INTO ENGLISH
mother is putting potatoes in the oven
INTO JAPANESE
母はジャガイモをオーブンに入れています
BACK INTO ENGLISH
mother is putting potatoes in the oven
You've done this before, haven't you.