what a beautiful girl she is

感叹句通常有what, how引导，表示赞美、惊叹、喜 悦、等感情。
what修饰名词，how 修饰形容词，副词或动词，感叹句结构主要有以下几种：

How +形容词+ a +名词+ 陈述语序
How+形容词或副词+ 陈述语序
What +名词+ 陈述语序
What+a+形容词+名词+ 陈述语序
What+ 形容词+复数名词+ 陈述语序
What+ 形容词+不可数名词+ 陈述语序

How clever a boy he is!
How lovely the baby is!
What noise they are making!
What a clever boy he is!
What wonderful ideas (we have)!
What cold weather it is!
感叹句的省略形式为：
What a clever boy (he is)!

right: how beautiful she is!

是的，是一定要省略。
how beautiful she is. 是对的。也可以是how beautiful the girl is .

请问HOW修ADJ是不是可以省咯名词？
如果有上下文，就可以
( how beautiful she is ) 和 what a beautiful girl she is