Have a partner hold you against the wall with a knife or come and stab and slash you and your job is to first relax and move with the knife as to survive (if the knife moves from up to down you move down with it in some way and adding another movement of your own) and finding out what in this movement lends itself to your survival. For example if you are against that wall and you have a knife pushed down between the shoulder and the neck slide down with the knife and let your knee raise and hit your partner so he is less concentrated where the knife is and dis aligned so you can avoid being stabbed and work on him better. If you are dragged backwards toward a car with a knife at your throat move your legs closer to the partner and since he is pulling it will be easy to break or lever his knees using his own drag force and moving away from the knife business side at the same time. Work slowly at first and add pushes and hits as you go to learn your responses and learn how to use them best and how to overcome them if need be. Remember the person you are working with has many flaws just like you and me and those are openings for you to work with. There is always an open door if you look with honest eyes.