YOU SAID:
A walrus ate my birthday cake.
INTO JAPANESE
ワタシが私の誕生日ケーキを食べた。
BACK INTO ENGLISH
Watashi ate my birthday cake.
INTO JAPANESE
ワタシは私のバースデーケーキを食べた。
BACK INTO ENGLISH
Watashi ate my birthday cake.
You've done this before, haven't you.