serious defects短语¹¹⁴⁴⁶⁷⁺⁴ 基本例句 🌏严重缺陷；严重疵点 But search engines have some serious defects. For example, so lots of pages returned by them are the same or similar. That is why people cannot get information rapidly and effectively. 通过搜索引擎能帮助用户获得所有与主题相关的页面，但返回的页面太多，而且有大量是重复和相似的，这样人们就不能快速获得自己真正所需要的信息。 fabiao