YOU SAID:
Can I have a potato please?
INTO JAPANESE
ジャガイモをお願いしますか?
BACK INTO ENGLISH
Would you like a potato?
INTO JAPANESE
ジャガイモが好きですか?
BACK INTO ENGLISH
Do you like potatoes?
INTO JAPANESE
あなたはジャガイモが好きですか?
BACK INTO ENGLISH
Do you like potatoes?
That didn't even make that much sense in English.