water-skiing和surfing有什么不同吗?

下面是这两项运动的英语定义：
Waterskiing is a sport where an individual is pulled behind a boat or a cable ski installation on a body of water,skimming the surface.
Surfing is a surface water sport.One way to understand the sport - is the definition the sport or pastime of being carried to the shore on the crest of large waves while standing or lying on some sort of board (i.e.longboard,short board,boogie board,wake board,etc.).
主要的区别是前者前面有船拖着,这个叫滑水
而后者主要是借助海浪的作用,这个叫冲浪

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本题考点： 实意动词