英语感叹句的变化规律.什么时候用what 什么时候用how如以下句子

（1）How tall the man is!=What a tall man!
（2）How tired he looks!
（3）How fast he drives!
(4) How many books dad has!
(5)How happy I am to meet you here!
(6)What a fine day!=How fine a day!
(7)What bad news!=How bad the news!
(8) How bad the weather is!=What bad weather!
(9)What a wonderful show!=How wonderful a show!
(10)How difficult the questions are!=What difficult questions!
以上是答案,下面是用法：
感叹句一般是用来表示说话时的喜悦、惊讶等情感.英语感叹句常用"what"和"how"引导,"what"和"how"与所修饰的词置于句首,其它部分用陈述句语序.
一、由"what"引导的感叹句："what"意为"多么"用作定语,修饰名词（被强调部分）,单数可数名词前要加不定冠词a/an,复数可数名词或不可数名词前不用冠词.这类句子的结构形式是：what+(a/an)+adj.+n.+主语+谓语+(itis).
如：①What a clever girl she is!
多么聪明的姑娘呀!
②What an interesting story it is!
多么有趣的故事呀!
③What good children they are!
他们是多么好的孩子呀!
④What beautiful flowers they are!
多么漂亮的花呀!
⑤What delicious food it is!
多么有味的食物呀!
⑥What heavy snow it is!
多么大的雪呀!
二、由"how"引导的感叹句："how"意为"多么",用作状语,修饰形容词或副词（被强调部分）.如果修饰形容词,则句中的谓语动词用系动词；如果how修饰副词,则句中的谓语动词用行为动词,这类句子的结构形式是：How+adj.（adv.）+主语+谓语+(itis).
如：①How cold it is today!
今天多么冷呀!
②How nice the pictures are!
多么漂亮的图画呀!
③How happy they look!
他们显得多么高兴呀!
④How well she sings!
她唱得多好呀!
⑤How hard they are working now!
他们干得多么起劲呀!
三、同义转换在表示同一意义时,英语感叹既可用"what"引导,也可用"how"引导.
如：①What a hot day it is!
How hot the day is !
多么热的天气呀!
②What tall buildings they are!
How tall the buildings are!
多么高的楼房呀!
③What bad weather it is!
How bad the weather is!
多么糟糕的天气呀!
④What bright sunshine it is!
How bright the sunshine is!
多么明亮的阳光呀!
四、感叹句在表示激动强烈的感情时,口语中常常采用省略句,其后面的主语和谓语往往略去不讲.
如：①What a fine day!
多么晴朗的天呀!
②What an honest boy!
多么诚实的孩子呀!
③What red apples!
多么红的苹果呀!
④How cool!
好凉快呀!
⑤How wonderful!
精彩极了!