what great fun we had making snowman

这是个由what引导的感叹句.感叹句要用倒装 .正常语序是：We had great fun making snowmen.这是have fun doing sth（做某事很开心）句型 .这个句子可不可以改成how 开头的形式捏不可以。因为修饰的不可数名词fun。