Running late to catch the bus, Luisa kicked a raised part of the sidewalk toes first. “Mierda!” She winced but managed to keep her balance. She stopped, raised her leg, and massaged her big toe through her canvas work shoes. Relieved to feel no broken bones, she lowered her foot, ignored the pain, and hurried to the bus stop. She shouldn’t have tripped, but that’s what happens when you’re not paying attention.