How to add minor tick marks to an axis besides its main tick marks?
<p>I have two questions.</p>

<ol>
<li>I was wondering how I can <strong>add</strong> <strong>two words</strong>, one appearing in place of <strong>"0",</strong> the other appearing in place of <strong>"10"</strong> on the X and Y axes while <strong>preserving the rest of the remaining numbers on the axes</strong> (i.e., 1 thru 9)?</li>
<li>How can I add <strong>minor tick marks</strong> to both axes?</li>
</ol>

<p>Here is <strong>my R code</strong>, with no success:</p>

<pre><code>plot(0:10,0:10,type="n",axes=FALSE,xlab="JBL",ylab="PRAC")

axis(side=1,at=c("AL",1,2,3,4,5,6,7,8,9,"BL"),las=1)
axis(side=2,at=c("CL",1,2,3,4,5,6,7,8,9,"DL"),las=1)
box()
</code></pre>