Google在Site title and description解释到了我们的疑问,内文说到:Google‘s generation of page titles and descriptions (or snippets) is completely automated and takes into account both the content of a page as well as references to it that appear on the web. Google对于标题与描述的产生是完全自动的,他会参考页面的内容以及该页面的参考资料来产生。