YOU SAID:
I have a potato in my luggage
INTO JAPANESE
私は荷物の中にジャガイモを持っています
BACK INTO ENGLISH
I have potatoes in my luggage.
INTO JAPANESE
私は荷物の中にジャガイモを持っています。
BACK INTO ENGLISH
I have potatoes in my luggage.
That didn't even make that much sense in English.