YOU SAID:
Do you know how many breads you've eaten?
INTO JAPANESE
どれだけのパンを食べたか知っていますか?
BACK INTO ENGLISH
Do you know how much bread you ate?
INTO JAPANESE
あなたがどれだけのパンを食べたか知っていますか?
BACK INTO ENGLISH
Do you know how much bread you ate?
That didn't even make that much sense in English.