on prep.在...之上；由...支撑着；在（某一天）；关于；基于adv.穿着；向前（移动)；表示持续性adj.表示已连接、处于工作状态或使用中；发生；值班
双语例句
Even people who spent just a few hours a week on the Internet experienced more depression and loneliness than those who logged on less frequently, the two-year study showed. 两年的研究表明，上网次数多的人与较少的人相比，即使是一周仅上网几小时也会经常地感觉到沮丧和孤独。
