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分人群分类，并向考官解释：

I guess it all depends on age. The youth are more likely to participate in competitive sports like basketball since they’re pretty energetic and they usually feel a sense of accomplishment if they finally win in a match. By contrast, elder generations are physically weaker, so they prefer some sports like square dancing which don’t require much strength or endurance.

利用相似的事物做类比：

Basketball now enjoys much popularity firstly because it’s quite easy to learn that we can easily get the hang of it. Besides that, it doesn’t cost much like some other sports like golf or horse-riding. Something worth mentioning is that there’s been a craze on basketball since 2002 when Yao Ming went to NBA and we all regard him as an idol.