Using Child Nodes And Looping Out Data?

I have two arrays. english() and french(), and each contain 10 quotes. I then have this HTML
Code:
<p><span class="pnum"> 1</span><span class="phrase"></span></p>
<p><span class="pnum"> 2</span><span class="phrase"></span></p>
<p><span class="pnum"> 3</span><span class="phrase"></span></p>
<p><span class="pnum"> 4</span><span class="phrase"></span></p>
<p><span class="pnum"> 5</span><span class="phrase"></span></p>
<p><span class="pnum"> 6</span><span class="phrase"></span></p>
<p><span class="pnum"> 7</span><span class="phrase"></span></p>
<p><span class="pnum"> 8</span><span class="phrase"></span></p>
<p><span class="pnum"> 9</span><span class="phrase"></span></p>
<p><span class="pnum">10</span><span class="phrase"></span></p>

Look at the comment in there to see what I need to do. I assume I would use .childNodes to get the end result, but I've never worked with nodes before, how would I reference the 2nd child (aka .phrase) and loop out the array in there?
Code:
function eventSource(e) {
var IE = document.attachEvent ? true:false;
var DOM = document.addEventListener ? true: false;
if (IE) return event.srcElement;
else if (DOM) return e.currentTarget;
}
function setUpTranslation() {
var phrases = document.getElementsByTagName("p");
for (var i=0; i < phrases.length; i++) {
//Here I need to reference the second child and change the inner content to french[i]
}}