 You just need to know the sudden signs. Look for FAST. F-A-S-T. F. Face drooping. A. Arm weakness. Or S. Speech difficulty. Then T. Time. Time to call 911 immediately. Because the sooner they get to the hospital, the sooner they'll get treatment. And that can make a remarkable difference in their recovery. Know the sudden signs. Face. Arm. Speech. Time. Spot a stroke. FAST.