这项运动要求极快的反应力。The sport requires very fast reactions.有经验的滑雪板运动员能够以极快的速度滑下山。Experienced snowboarders can zip downhill amazingly fast.那辆车以极快的速度驶过.The car rattled along at great speed....

“极快的”的英语可以翻译为：splitting，prestissimo ...