感叹句不能说有没有时态,那要看你是要表达什么时间的感情,是表达现在的感情就是现在时.
说明一下,感叹句要么是用How修饰形容词,要么用What修饰名词,She is reading a very interesting book.这一句要改成感叹句,很明显只能是用How来修饰interesting,或者用what修饰book,非别是How interesting the book （whichthat) she is reading!What an interesting book （whichthat） she is reading!