How 引导的感叹句，有三种句子结构：
① How+adj/adv+主+谓
如: How careful she is !
How fast he runs!
② How +adj+a/an +可数名词单数+主+谓
如：How beautiful a girl she is !
③ How +主+谓
如：How time flies!。
How 引导的感叹句，有三种句子结构：
① How+adj/adv+主+谓
如: How careful she is !
How fast he runs!
② How +adj+a/an +可数名词单数+主+谓
如：How beautiful a girl she is !
③ How +主+谓
如：How time flies!。
