YOU SAID:
this is Piece Of Cake!
INTO JAPANESE
これはケーキのピースです!
BACK INTO ENGLISH
This is a piece of cake!
INTO JAPANESE
これはケーキの一部です!
BACK INTO ENGLISH
This is part of the cake!
INTO JAPANESE
これはケーキの一部です!
BACK INTO ENGLISH
This is part of the cake!
That didn't even make that much sense in English.