YOU SAID:

i can't beleive you've done this

INTO JAPANESE

私はあなたがこれをやったとは信じられない

BACK INTO ENGLISH

I can not believe that you did this

INTO JAPANESE

私はあなたがこれをしたとは信じられない

BACK INTO ENGLISH

I can not believe you did this

INTO JAPANESE

私はあなたがこれをしたとは信じられない

BACK INTO ENGLISH

I can not believe you did this