I’m talking to you from the Hilltop School Skating Marathon(马拉松溜冰). Here, students are skating to raise money for charity（慈善）. For every hour they skate, each student raises（挣得） ten yuan for charity. The skating marathon has been going for five hours now, and several skatersare still skating. Alison was the first one to start, and has been skating for the whole five hours. Next is Sam, and he has been skating for four hours. Lu Ning has been skating for four hours too, and Li Chen just started an hour ago.