题目内容：

It's great ______ to play with my pet(fun funny)

优质解答

fun 这是it语句,it为形式主语,后面的to do 结构才是是真正的主语,这样做是为了避免语句给人头重脚轻的感觉.而且fun在这儿是名词,由形容词great修饰,funny也是形容词,所以不能用.It is really funny to play with my pet.