He had just scrambled over an 800-pound boulder when it came loose and sent the young man flying down the canyon wall.

• 就在他攀上一块重达800磅的大山石时，山石突然松动了，小伙子立即松手，惯性把他一下子就甩到岩壁上，山石同时向他滚来，压到他的右臂后才停了下来。