Minor doc fixes.
diff --git a/Doc/library/collections.rst b/Doc/library/collections.rst
index 41b4eba..32cc639 100644
--- a/Doc/library/collections.rst
+++ b/Doc/library/collections.rst
@@ -206,7 +206,7 @@
.. method:: most_common([n])
Return a list of the *n* most common elements and their counts from the
- most common to the least. If *n* not specified, :func:`most_common`
+ most common to the least. If *n* is not specified, :func:`most_common`
returns *all* elements in the counter. Elements with equal counts are
ordered arbitrarily::