diff --git a/spec/formatting.md b/spec/formatting.md
index 2f40057ee3..75dc313c3b 100644
--- a/spec/formatting.md
+++ b/spec/formatting.md
@@ -31,33 +31,39 @@ refer to a local variable that's defined after it in the message.
 
 ## Pattern Selection
 
-When formatting a message with one or more _selectors_,
-the _pattern_ of one of the _variants_ must be selected for formatting.
-
-When a message has a single _selector_,
-an implementation-defined method compares each key to the _selector_
-and determines which of the keys match, and in what order of preference.
-The list of keys passed to this implementation-defined method
-does not include the catch-all key `*`.
-The catch-all key `*` is treated as a match for any _selector_,
-but with the lowest possible preference.
-
-In a message with more than one _selector_,
-the number of keys in each _variant_ **_must_** equal the number of _selectors_.
-These correspond to _selectors_ by position.
-The same implementation-defined method as above is used to compare
-the corresponding key of each _variant_ to its _selector_,
-to determine which of the keys match, and in what order of preference.
-In order to select a single _variant_,
-the full list of _variants_ will need to be filtered and sorted.
-First, each _variant_ with a key that does not match its _selector_ is left out.
-Then, the remaining _variants_ are sorted lexicographically by key preference,
-with earlier _selectors_ having higher priority than later ones.
-Finally, the highest-sorted _variant_ is selected.
+When a _message_ contains a _match_ statement with one or more _expressions_,
+the implementation needs to determine which _variant_ will be used
+to provide the _pattern_ for the formatting operation. 
+This is done by ordering and filtering the available _variant_ statements according to their _key_ values
+and selecting the first one.
+
+The number of _keys_ in each _variant_ **_MUST_** equal the number of _expressions_ in the _selectors_.
+
+Each _key_ corresponds to an _expression_ in the _selectors_ by its position in the _variant_.
+
+> For example, in this message:
+> ```
+> match {:one} {:two} {:three}
+> when  1 2 3 { ... }
+> ```
+> The first _key_ `1` corresponds to the first _expression_ in the _selectors_ (`{:one}`),
+> the second _key_ `2` to the second _expression_ (`{:two}`), 
+> and the third _key_ `3` to the third _expression_ (`{:three}`).
+
+To determine which _variant_ best matches a given set of inputs,
+each _selector_ is used in turn to order and filter the list of _variants_.
+
+Each _variant_ with a _key_ that does not match its corresponding _selector expression_
+is omitted from the list of _variants_. 
+The remaining _variants_ are sorted according to the _expression_'s _key_-ordering preference.
+Earlier _expressions_ in the _selector_'s list of _expressions_ have a higher priority than later ones. 
+
+When all of the _selector expressions_ have been processed,
+the earliest-sorted _variant_ in the remaining list of _variants_ is selected.
 
 This selection method is defined in more detail below.
-An implementation MAY use any pattern selection method,
-as long as its observable behaviour matches the results of the method defined here.
+An implementation **_MAY_** use any pattern selection method,
+as long as its observable behavior matches the results of the method defined here.
 
 ### Resolve Selectors