YOU SAID:
Didn't know she did that
INTO JAPANESE
彼女がそれをやったことを知らなかった
BACK INTO ENGLISH
I didn't know she did it
INTO JAPANESE
彼女がやったことは知らなかった
BACK INTO ENGLISH
I didn't know what she did
INTO JAPANESE
私は彼女が何をしたのか知りませんでした
BACK INTO ENGLISH
I didn't know what she did
You've done this before, haven't you.