YOU SAID:
i dont know what to do tommorow
INTO JAPANESE
私はtommorowに何をすべきかわからない
BACK INTO ENGLISH
I do not know what to do for tommorow
INTO JAPANESE
私はtommorowのために何をすべきかわからない
BACK INTO ENGLISH
I do not know what to do for tommorow
That didn't even make that much sense in English.