The separator element introduced contributes no information to the document yet must be there for the document to be valid.
引入的separator元素不能提供任何文档信息，但是为了让文档有效，它必须出现在这里。
Because the separator element must appear in the instance there is no ambiguity between content which matches the separator element declaration and the wildcard which follows it.
由于separator元素必须出现在实例中，所以在匹配separator元素声明的内容和它后面的通配符之间不存在含糊性。
One more small step from presentation markup to structural markup is the renaming of the hr element to separator.
从表示标记到结构型标记还要一小步，把 hr 元素重命名为 separator。
应用推荐