title: Regex pattern to find a term's existence in last 3 words of another term in a string
body: <p>Need to write RegEx in C# for the below req.</p>
  
  <p><strong>Input - A String, Term 1 (No), Term 2 (Alcohol)</strong></p>
  
  <p>I want to find out, if a term like "not" is present in last 2 or 3 words before  term like "alcohol".</p>
  
  <pre><code>1. String : I am not taking alcohol these days.
  </code></pre>
  
  <p>Answer - Yes</p>
  
  <pre><code>2. String : I am not feeling like taking alcohol these days.
  </code></pre>
  
  <p>Answer - No</p>
  
  <p>I tried something like below, but its not working :</p>
  
  <pre><code>Regex.IsMatch(textLine, @"(^|\s)" + negativeTerm + @"(\s|$)", RegexOptions.IgnoreCase)
  </code></pre>