used value -> used values

Author: fantasai

css3-page/Overview.src.html

@@ -2001,7 +2001,7 @@ <h3 id="allowed-pg-brk">Allowed page breaks</h3>
 <ol>
 <li id="brk-btw-blocks">In the vertical margin between sibling block boxes
 (or rows in a table). When a <a href="forced-pg-brk">forced page break</a>
-occurs here, the used value of any adjoining 'margin-bottom' are set to zero.
+occurs here, the used values of any adjoining 'margin-bottom' are set to zero.
 When an unforced page break occurs here, both the adjoining 'margin-top' and
 'margin-bottom' are set to zero.</li>
 <li id="brk-btw-lines">Between line boxes inside a block box.</li>