YOU SAID:
hello i am going to leave
INTO JAPANESE
こんにちは私は出発するつもりです
BACK INTO ENGLISH
Hello I am leaving
INTO JAPANESE
こんにちは私は出発します
BACK INTO ENGLISH
Hello I will leave
INTO JAPANESE
こんにちは私は残します
BACK INTO ENGLISH
Hello I will leave
That didn't even make that much sense in English.