1.What 在句首起强调作用,强调去野餐这件事好!如果强调天气好就是How funny...
真正的主语是“去野餐“这件事 即What fun it is to go for a picnic
写成一般句也就是：It is fun to go for a picnic on such a fine day.
2.such as 是“例如” 后面一般跟短语和单词,在这里做插入语,补充说明作用..
like 作为动词谓语,要和主语连用!如果将第一个“,”去掉,那就能用
即Many people like teachers and students,like reading very mush.