title: Converting BNF to EBNF
body: <p>I need to know how to convert the next BNF to EBNF so it will help me understand more how they work</p>
  
  <pre><code>S-&gt; aI1I2 | epsilon
  I1-&gt; I1e | b
  I2-&gt; cd | cS
  </code></pre>
  
  <p>note: epsilon means the empty set</p>