YOU SAID:
I ate cheese and cereal for breakfast
INTO JAPANESE
朝食はチーズとシリアルを食べた。
BACK INTO ENGLISH
I ate cheese and cereal for breakfast.
INTO JAPANESE
私は朝食にチーズとシリアルを食べた。
BACK INTO ENGLISH
I ate cheese and cereal for breakfast.
That didn't even make that much sense in English.