YOU SAID:
She going to throw it back
INTO JAPANESE
彼女はそれを投げ捨てるつもりだ
BACK INTO ENGLISH
She is going to throw it away
INTO JAPANESE
彼女はそれを投げ捨てるつもりです
BACK INTO ENGLISH
She will throw it away
INTO JAPANESE
彼女はそれを捨てる
BACK INTO ENGLISH
She throws it away
INTO JAPANESE
彼女はそれを投げ捨てる
BACK INTO ENGLISH
She throws it away
That didn't even make that much sense in English.