title: Extract the consecutive words from the middle of a string in R
body: <p>Ok, so I'm new to regexpr and my brain is about to fry. What I would like to do is extract words two and three from a string. For example:</p>
  
  <pre><code>sentence &lt;- "Certified 2017 Mazda CX-5 AWD Touring"
  TheFunction(sentence)
  </code></pre>
  
  <p>should return "2017 Mazda"</p>
  
  <p>My initial attempt is using something like:</p>
  
  <pre><code>sub("\\s\\S+\\s\\S+\\s", "\\1", sentence)
  </code></pre>
  
  <p>but is failing miserably. My idea is to find the first pattern that matches "space-word-space-word-space"</p>