What fun it is 中fun是什么 (表语吗)那名词在句中充当什么成分?名词性表语?主语?

如题What fun it is中fun是什么 what a fun和how fun的用法是what a fun it is to do sth还是how fun ? 英语的fun可数吗?是What a great fun it is!还是What great fun it is! what fun day it is?为什么用fun,不用funny what fun it is to listen music 这里的fun为什么不能是形容词用how fun. what fun it is! 这个fun前面是不是要加a或者what改fun? What a ____(fun)story it is! what fun it is to=how____ 为什么是what fun it is to. fun 这是一件好玩的事it is fun 为什么是what great fun it is!而不是what a great fun it is! what is your fun fun what is this? it's fun to do 换成 感叹句是what fun 还是 how funit's fun to play with them=______ _______ it is to play with them. fun 是什么词性It is gueat fun 中great fun 可以用interesting代替吗 ___great fun it is What fun it is 和How fun it is 后面加doing还是to do What fun it is How fun it is ,怎么用,仔细点