YOU SAID:
You've done this, have you not.
INTO JAPANESE
あなたはこれをしましたね。
BACK INTO ENGLISH
You did this
INTO JAPANESE
あなたはこれをしました
BACK INTO ENGLISH
you did this
INTO JAPANESE
あなたはこれをしました
BACK INTO ENGLISH
you did this
That didn't even make that much sense in English.