better handling of multi-word phrase pluralization

utils/word-problems.js

@@ -31,7 +31,7 @@ jQuery.extend( KhanUtil, {
 	// - plural(NUMBER, singular, plural): 
 	//		- return "NUMBER word"
 	plural: (function() {
-		var one_offs = {
+		var oneOffs = {
 			'quiz': 'quizzes',
 			'shelf': 'shelves',
 			'loaf': 'loaves',
@@ -46,46 +46,53 @@ jQuery.extend( KhanUtil, {
 			// determine if our word is all caps.  If so, we'll need to
 			// re-capitalize at the end
 			var isUpperCase = (word.toUpperCase() == word);
-			var one_off = one_offs[word.toLowerCase()];
+			var oneOff = oneOffs[word.toLowerCase()];
 			var words = word.split(/\s+/);
 
 			// first handle simple one-offs
-			if ( one_off ) {
-				word = one_off;
+			if ( oneOff ) {
+				return oneOff;
 			}
 
-			// for 3-word phrases where the middle word is 'in' or 'of',
-			// pluralize the first word
-			else if ( words.length == 3 && /\b(in|of)\b/i.test(words[1]) ) {
-				words[0] = KhanUtil.plural( words[0] );
-				return words.join(" ");
-			}
+			// multiple words
+			else if ( words.length > 1 ) {
+				// for 3-word phrases where the middle word is 'in' or 'of',
+				// pluralize the first word
+				if ( words.length == 3 && /\b(in|of)\b/i.test(words[1]) ) {
+					words[0] = KhanUtil.plural( words[0] );
+				}
 
-			// if two words, pluralize the second word
-			else if ( words.length == 2 ) {
-				words[1] = KhanUtil.plural( words[1] );
-				return words.join(" ");
-			}
+				// otherwise, just pluraize the last word
+				else {
+					words[ words.length-1 ] = 
+						KhanUtil.plural( words[ words.length-1 ] );
+				}
 
-			// "-y" => "-ies"
-			else if ( /[^aeiou]y$/i.test( word ) ) {
-				word = word.replace(/y$/i, "ies");
+				return words.join(" ");
 			}
 
-			// add "es"; things like "fish" => "fishes"
-			else if ( /[sxz]$/i.test( word ) || /[bcfhjlmnqsvwxyz]h$/.test( word ) ) {
-				word += "es";
-			} 
-
-			// all the rest, just add "s"
+			// single words
 			else {
-				word += "s";
-			}
+				// "-y" => "-ies"
+				if ( /[^aeiou]y$/i.test( word ) ) {
+					word = word.replace(/y$/i, "ies");
+				}
 
-			if ( isUpperCase ) {
-				word = word.toUpperCase();
+				// add "es"; things like "fish" => "fishes"
+				else if ( /[sxz]$/i.test( word ) || /[bcfhjlmnqsvwxyz]h$/.test( word ) ) {
+					word += "es";
+				} 
+
+				// all the rest, just add "s"
+				else {
+					word += "s";
+				}
+
+				if ( isUpperCase ) {
+					word = word.toUpperCase();
+				}
+				return word;
 			}
-			return word;
 		};
 
 		return function(value, arg1, arg2) {