have good fun doing sth为什么用doing?

have good fun doing sth为什么用doing? have fun doing sth. have fun doing sth have a good time和have fun后为什么要跟doing sth have good fun doing sth和have fun doing一样吗? have fun doing sth =enjoy oneself doing sth=have a good/grea have fun doing sth造句 用 have fun doing Sth.Have a good time Play happy Enjoy mysel have fun doing sth.还是 have fun to do sth. have fun doing sth 还是have fun to do sth? have fun doing sth.用这种形式造句 have fun doing sth 什么意思