Add note to 3.1.2 Language of Parts to clarify single words can be phrases/passages

understanding/20/language-of-parts.html

@@ -22,12 +22,18 @@ <h2>In brief</h2>
       <h2>Intent of Language of Parts</h2>
 
       <p>The intent of this success criterion is to ensure that user agents can correctly present
-         phrases, passages, and in some cases words written in multiple languages. This makes it possible for user agents and
+         phrases or passages written in multiple languages. This makes it possible for user agents and
          assistive technologies to present content according to the  presentation and pronunciation
          rules for that language. This applies to graphical browsers as well as screen readers,
          braille displays, and other voice browsers.
       </p>
 
+      <div class="note">
+         <p>Phrases and passages consist of <em>one or more words</em>. As a result, even an individual
+            word can be subject to the requirements of this criterion, unless it falls under one of the
+            exceptions.</p>
+      </div>
+
       <p>Both assistive technologies and conventional user agents can render text more accurately
          if the language of each passage of text is identified. Screen readers can use the
          pronunciation rules of the language of the text. Visual browsers can display characters