title: jQuery Select first and second td
body: <p>How can I add a class to the first and second td in each tr?</p>
  
  <pre><code>&lt;div class='location'&gt;
  &lt;table&gt;
  &lt;tbody&gt;
  &lt;tr&gt;
  &lt;td&gt;THIS ONE&lt;/td&gt;
  &lt;td&gt;THIS ONE&lt;/td&gt;
  &lt;td&gt;else&lt;/td&gt;
  &lt;td&gt;here&lt;/td&gt;
  &lt;/tr&gt;
  &lt;tr&gt;
  &lt;td&gt;THIS ONE&lt;/td&gt;
  &lt;td&gt;THIS ONE&lt;/td&gt;
  &lt;td&gt;else&lt;/td&gt;
  &lt;td&gt;here&lt;/td&gt;
  &lt;/tr&gt;
  &lt;/tbody&gt;
  &lt;/table&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>For the first td, this does nothing?</p>
  
  <pre><code>$(".location table tbody tr td:first-child").addClass("black");
  </code></pre>
  
  <p>Can I also use second-child?</p>