YOU SAID:
Did you have a brain tumor for breakfast?
INTO JAPANESE
朝食に脳腫瘍がありましたか?
BACK INTO ENGLISH
Did you have a brain tumor at breakfast?
INTO JAPANESE
朝食時に脳腫瘍がありましたか?
BACK INTO ENGLISH
Did you have a brain tumor at breakfast?
That didn't even make that much sense in English.