it's fun doing中的fun 是adj it's fun to do 是n .这种说法对吗?

问题描述:

it's fun doing中的fun 是adj it's fun to do 是n .这种说法对吗?

have fun doing显然,这里的fun是名词,即第一个has fun doing中,fun为名词(it has fun doing)
第二个,fun 为不可数名词,例如,It is great fun to play with you.