YOU SAID:
My favorite color is banana
INTO JAPANESE
私の好きな色はバナナ
BACK INTO ENGLISH
Banana is my favorite color
INTO JAPANESE
バナナは私の好きな色
BACK INTO ENGLISH
Banana is my favorite color.
INTO JAPANESE
バナナは、私の好きな色です。
BACK INTO ENGLISH
Banana is my favorite color.
That didn't even make that much sense in English.