YOU SAID:
who was i when i was eating you yesterday
INTO JAPANESE
昨日あなたを食べていたときは誰だった私
BACK INTO ENGLISH
Yesterday you were eating was who I
INTO JAPANESE
昨日あなたが食べていたのは私でした
BACK INTO ENGLISH
It was me that you were eating yesterday
INTO JAPANESE
それは昨日食べていた私だった
BACK INTO ENGLISH
It was me that I ate yesterday.
INTO JAPANESE
昨日食べたのは私でした。
BACK INTO ENGLISH
It was me who ate yesterday.
INTO JAPANESE
昨日食べたのは私でした。
BACK INTO ENGLISH
It was me who ate yesterday.
That didn't even make that much sense in English.