说明：  SMIL和HTML语言的语法格式非常相像！所以，如果大家对HTML熟悉的话，SMIL学习起来就很容易。但是，二者的差别是很大的，所以如果想学的很好，大家一定要认真地学
(SMIL and HTML language syntax format is very similar! So, if you are familiar with HTML, SMIL learning is very easy. However, the difference between the two is very big, so if you want to learn very good, we must carefully study)