title: Add text to beginning of line if a string is present in that line
body: <p>I am using Notepad++ and working with a huge log file of about 400MB. Is it possible to place a particular text at the beginning of a line, if a certain string is present in that particular line?
  For example:</p>
  
  <p>Input</p>
  
  <pre><code>This is a sentence
  This is a sentence
  This is the sentence
  This is a sentence
  </code></pre>
  
  <p>I want to have the text YES in front of a line featuring the word 'the'</p>
  
  <p>Output</p>
  
  <pre><code> This is a sentence
   This is a sentence
   YES This is the sentence
   This is a sentence
  </code></pre>