首先你要清楚fun作为名词和形容词各自的含义: fun当名词时, 当“享乐,乐趣,快乐,享乐的事”的意思讲时, 有be fun doing eg: It's not much fun going to a party on your own. (独自一人参加聚会没什么意思) fun当形容词时, 当“逗乐的,有趣的,使人开心的”的意思讲时, 有be fun to do eg: She's really fun to be with. (和她在一起真开心) 本句后面是不定式,所以确定fun在这里是形容词,所以选A。追问
be fun doing 里,fun是名词吗?be动词后可以加名词吗?
追答
你看上面例句It's not much fun going to a party on your own. fun前面是形容词much,再前面不就是be动词嘛,因为fun是不可数名词,所以前面不就冠词a /an。