simplify the intro paragraphs

Author: nedbat

Doc/library/index.rst

@@ -4,14 +4,15 @@
   The Python standard library
 ###############################
 
-While :ref:`reference-index` describes the exact syntax and
+This library reference manual describes the standard library
+distributed with Python. It also describes some of the optional
+components that are commonly included in Python distributions.
+
+Elsewhere, :ref:`reference-index` describes the exact syntax and
 semantics of the Python language, and :ref:`builtins-index` describes
-the built-ins, this library reference manual
-describes the standard library that is distributed with Python. It also
-describes some of the optional components that are commonly included
-in Python distributions.
+the built-in functions.
 
-Python's standard library is very extensive, offering a wide range of
+Python's standard library is extensive, offering a wide range of
 facilities as indicated by the long table of contents listed below. The
 library contains built-in modules (written in C) that provide access to
 system functionality such as file I/O that would otherwise be

Doc/reference/index.rst

@@ -5,9 +5,11 @@
 #################################
 
 This reference manual describes the syntax and core semantics of the
-language. It is terse, but attempts to be exact and complete. The semantics of
-built-in object types and of the built-in functions and modules
-are described in :ref:`builtins-index` and :ref:`library-index`.
+language. It is terse, but attempts to be exact and complete.
+
+Elsewhere, the built-in object types and functions are described in
+:ref:`builtins-index`. Standard library modules are described in :ref:`library-index`.
+
 For an informal introduction to the
 language, see :ref:`tutorial-index`. For C or C++ programmers, two additional
 manuals exist: :ref:`extending-index` describes the high-level picture of how to