权威例句
Football helmetFootball helmetFootball helmetAmerican football protective equipment, American football, Canadian footballHistory of the football helmetWinged football helmetHelmet cams, sideline computers coming to college footballDevelopment of the STAR Evaluation System for Football Helmets: Integrating Player Head Impact Exposure and Risk of ConcussionFootball helmet, testing method, and testing apparatusFootball helmet having a removable inflatable liner and a method for making the sameNational Operating Committee on Standards for Athletic Equipment football helmet certification program.Birth and evolution of the football helmet.Do football helmets reduce acceleration of impact in blunt head injuries?
