Splitting String and Merging POP

##PHP Code
//Divides String after amount of spaces between words + 1
$arr = explode(" ",$contents,100+1);
//Grabs the the end of the array value.
$last = array_pop($arr);
//Compile all the strings again into one.
$contents = implode(" ",$arr)." ".'<a href="">Read More...</a></p><div class="content_more" style="display:none">'." ".$last."</div>";

//Notice the open paragraph tag.
<div class="rower2 rb">
<p>
    $contents
</div>

//HTML Output
<p>
The start of the content post. More content here.
<a href="">Read More...</a>
</p>
<div class="content_more" style="display:none">
The rest of the contents.
</div>