Combine lists horizontally in emacs
<p>How can I combine lists like these: </p>

<p>(list A in the buffer)</p>

<pre><code>apple
business
car
</code></pre>

<p>(list B in the clipboard)</p>

<pre><code>sauce
school
driving
</code></pre>

<p>to get a result like this? :</p>

<p>(if I run some function at the end of the element "boy" in the list A)</p>

<pre><code>apple sauce
business school
car driving
</code></pre>