What an exciting news.为什么要加an啊?

What an exciting news.为什么要加an啊? What an exciting news it is.为什么news能加an呢? ———exciting news 前面要填WHAT AN或者WHAT 为什么不能填WHAT AN哦 what an exciting news求解正误 WHAT an exciting news they have told me!这样解释为什么可以用AN对吗? What an exciting news they have told me! 是 a exciting news还是 an exciting news? what amazing news?为什么不用what an amazing news? Really?-------------exciting news!A.What B.What an C.How D.H 英语感叹句问题.（ ） exciting news is it 填 How 、What 、还是 What an 或是别的 What an (exciting) story it is!填exciting的依据是什么?回答对了加赏! what|what an|how|how an exciting moment!选哪个