这有点特殊，但是我正在使用的应用程序仅实现了正则表达式参数的有限子集。最重要的是，它不支持除基本括号分组以外的任何组选项（即，没有命名的组，没有先行或后备的搜索，甚至没有(?:)）。
我只希望获得TRUE / FALSE匹配项，不需要提取，替换或解析数据，我只需要知道指定的模式是否出现在主题字符串，是或否。
因此，我正在尝试使用基本的正则表达式构建一个模式，该模式将从文本块中找到4个提供的术语中的3个，并且可以按任意顺序触发匹配。
为方便起见，我尝试了以下操作：(\b(Term1|Term2|Term3|Term4)\b.*?){3,}，但是它不起作用。奇怪的是，如果我将{3,}更改为{1,}，它将找到每个术语的 all 个实例，表明该模式确实有效，但是当我告诉它时，我只想要一个匹配项是3个或更多实例，则找不到其中的任何。即使当我在Regex101上尝试该模式时也是如此，因此，这似乎不是我的应用程序内的引擎有限的故障。
在使用模式/b(TermX)/b时，主题文本中的所有单词都在其前后加上至少一个空格或句点，并且确实匹配。在一个样本数据中，将量词转换为{1,}时发现9个匹配项，但是当将其更改为{3,}时为零！
我对此模式缺少什么/误解？
编辑：返回到我要处理的有限功能集：我 only 能够指定模式。据我所知，没有提供用于指定条件（即不区分大小写，全局，多行，单行等）的机制，而且似乎没有默认设置这些条件。
修改：根据请求提供示例数据...
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<p><span style="text-decoration: underline;"><strong>EXPIRATION
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This is a optimization offer for your website. You are under no obligation
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