diff --git a/Doc/distutils/packageindex.rst b/Doc/distutils/packageindex.rst
index daf9345..2d7daef 100644
--- a/Doc/distutils/packageindex.rst
+++ b/Doc/distutils/packageindex.rst
@@ -167,7 +167,7 @@
     username: <username>
     password: <password>
 
-The *distutils* section defines a *index-servers* variable that lists the
+The *distutils* section defines an *index-servers* variable that lists the
 name of all sections describing a repository.
 
 Each section describing a repository defines three variables:
diff --git a/Doc/howto/descriptor.rst b/Doc/howto/descriptor.rst
index f018b0e..530f34b 100644
--- a/Doc/howto/descriptor.rst
+++ b/Doc/howto/descriptor.rst
@@ -319,7 +319,7 @@
 patterns of binding functions into methods.
 
 To recap, functions have a :meth:`__get__` method so that they can be converted
-to a method when accessed as attributes.  The non-data descriptor transforms a
+to a method when accessed as attributes.  The non-data descriptor transforms an
 ``obj.f(*args)`` call into ``f(obj, *args)``.  Calling ``klass.f(*args)``
 becomes ``f(*args)``.
 
diff --git a/Doc/install/index.rst b/Doc/install/index.rst
index 8f3ad72..2d83079 100644
--- a/Doc/install/index.rst
+++ b/Doc/install/index.rst
@@ -148,7 +148,7 @@
 
 On Windows, you'd probably download :file:`foo-1.0.zip`.  If you downloaded the
 archive file to :file:`C:\\Temp`, then it would unpack into
-:file:`C:\\Temp\\foo-1.0`; you can use either a archive manipulator with a
+:file:`C:\\Temp\\foo-1.0`; you can use either an archive manipulator with a
 graphical user interface (such as WinZip) or a command-line tool (such as
 :program:`unzip` or :program:`pkunzip`) to unpack the archive.  Then, open a
 command prompt window and run::
diff --git a/Doc/library/asyncio-protocol.rst b/Doc/library/asyncio-protocol.rst
index 698d2bf..e714488 100644
--- a/Doc/library/asyncio-protocol.rst
+++ b/Doc/library/asyncio-protocol.rst
@@ -148,7 +148,7 @@
       high-water limit.  Neither *high* nor *low* can be negative.
 
       The defaults are implementation-specific.  If only the
-      high-water limit is given, the low-water limit defaults to a
+      high-water limit is given, the low-water limit defaults to an
       implementation-specific value less than or equal to the
       high-water limit.  Setting *high* to zero forces *low* to zero as
       well, and causes :meth:`pause_writing` to be called whenever the
diff --git a/Doc/library/contextlib.rst b/Doc/library/contextlib.rst
index e567549..2b2cece 100644
--- a/Doc/library/contextlib.rst
+++ b/Doc/library/contextlib.rst
@@ -142,7 +142,7 @@
    is hardwired to stdout.
 
    For example, the output of :func:`help` normally is sent to *sys.stdout*.
-   You can capture that output in a string by redirecting the output to a
+   You can capture that output in a string by redirecting the output to an
    :class:`io.StringIO` object::
 
         f = io.StringIO()
diff --git a/Doc/library/email.parser.rst b/Doc/library/email.parser.rst
index ec74fe0..177adc6 100644
--- a/Doc/library/email.parser.rst
+++ b/Doc/library/email.parser.rst
@@ -146,7 +146,7 @@
       methods on file-like objects.
 
       The text contained in *fp* must be formatted as a block of :rfc:`2822`
-      style headers and header continuation lines, optionally preceded by a
+      style headers and header continuation lines, optionally preceded by an
       envelope header.  The header block is terminated either by the end of the
       data or by a blank line.  Following the header block is the body of the
       message (which may contain MIME-encoded subparts).
@@ -189,7 +189,7 @@
       methods on file-like objects.
 
       The bytes contained in *fp* must be formatted as a block of :rfc:`2822`
-      style headers and header continuation lines, optionally preceded by a
+      style headers and header continuation lines, optionally preceded by an
       envelope header.  The header block is terminated either by the end of the
       data or by a blank line.  Following the header block is the body of the
       message (which may contain MIME-encoded subparts, including subparts
diff --git a/Doc/library/gzip.rst b/Doc/library/gzip.rst
index ce02077..355cf9c 100644
--- a/Doc/library/gzip.rst
+++ b/Doc/library/gzip.rst
@@ -64,7 +64,7 @@
    method.  At least one of *fileobj* and *filename* must be given a non-trivial
    value.
 
-   The new class instance is based on *fileobj*, which can be a regular file, a
+   The new class instance is based on *fileobj*, which can be a regular file, an
    :class:`io.BytesIO` object, or any other object which simulates a file.  It
    defaults to ``None``, in which case *filename* is opened to provide a file
    object.
diff --git a/Doc/library/pickle.rst b/Doc/library/pickle.rst
index 08618fa..3305195 100644
--- a/Doc/library/pickle.rst
+++ b/Doc/library/pickle.rst
@@ -192,7 +192,7 @@
    number is specified, :data:`HIGHEST_PROTOCOL` is selected.
 
    The *file* argument must have a write() method that accepts a single bytes
-   argument.  It can thus be an on-disk file opened for binary writing, a
+   argument.  It can thus be an on-disk file opened for binary writing, an
    :class:`io.BytesIO` instance, or any other custom object that meets this
    interface.
 
@@ -288,7 +288,7 @@
    number is specified, :data:`HIGHEST_PROTOCOL` is selected.
 
    The *file* argument must have a write() method that accepts a single bytes
-   argument.  It can thus be an on-disk file opened for binary writing, a
+   argument.  It can thus be an on-disk file opened for binary writing, an
    :class:`io.BytesIO` instance, or any other custom object that meets this
    interface.
 
diff --git a/Doc/library/socket.rst b/Doc/library/socket.rst
index 80d5811..8577c3c 100644
--- a/Doc/library/socket.rst
+++ b/Doc/library/socket.rst
@@ -762,7 +762,7 @@
 
 .. function:: sethostname(name)
 
-   Set the machine's hostname to *name*.  This will raise a
+   Set the machine's hostname to *name*.  This will raise an
    :exc:`OSError` if you don't have enough rights.
 
    Availability: Unix.
@@ -794,7 +794,7 @@
 
 .. function:: if_indextoname(if_index)
 
-   Return a network interface name corresponding to a
+   Return a network interface name corresponding to an
    interface index number.
    :exc:`OSError` if no interface with the given index exists.
 
diff --git a/Doc/library/tokenize.rst b/Doc/library/tokenize.rst
index bd6b121..c9cb518 100644
--- a/Doc/library/tokenize.rst
+++ b/Doc/library/tokenize.rst
@@ -41,7 +41,7 @@
    returned as a :term:`named tuple` with the field names:
    ``type string start end line``.
 
-   The returned :term:`named tuple` has a additional property named
+   The returned :term:`named tuple` has an additional property named
    ``exact_type`` that contains the exact operator type for
    :data:`token.OP` tokens.  For all other token types ``exact_type``
    equals the named tuple ``type`` field.
diff --git a/Doc/library/unittest.rst b/Doc/library/unittest.rst
index 1930f78..a8d9f53 100644
--- a/Doc/library/unittest.rst
+++ b/Doc/library/unittest.rst
@@ -464,7 +464,7 @@
 .. versionadded:: 3.1
 
 Unittest supports skipping individual test methods and even whole classes of
-tests.  In addition, it supports marking a test as a "expected failure," a test
+tests.  In addition, it supports marking a test as an "expected failure," a test
 that is broken and will fail, but shouldn't be counted as a failure on a
 :class:`TestResult`.
 
diff --git a/Doc/library/urllib.request.rst b/Doc/library/urllib.request.rst
index cd4690f..74f3c1f 100644
--- a/Doc/library/urllib.request.rst
+++ b/Doc/library/urllib.request.rst
@@ -1322,7 +1322,7 @@
     .. method:: retrieve(url, filename=None, reporthook=None, data=None)
 
        Retrieves the contents of *url* and places it in *filename*.  The return value
-       is a tuple consisting of a local filename and either a
+       is a tuple consisting of a local filename and either an
        :class:`email.message.Message` object containing the response headers (for remote
        URLs) or ``None`` (for local URLs).  The caller must then open and read the
        contents of *filename*.  If *filename* is not given and the URL refers to a
diff --git a/Doc/library/xml.dom.minidom.rst b/Doc/library/xml.dom.minidom.rst
index dcd030c..6762e91 100644
--- a/Doc/library/xml.dom.minidom.rst
+++ b/Doc/library/xml.dom.minidom.rst
@@ -54,7 +54,7 @@
 
 .. function:: parseString(string, parser=None)
 
-   Return a :class:`Document` that represents the *string*. This method creates a
+   Return a :class:`Document` that represents the *string*. This method creates an
    :class:`io.StringIO` object for the string and passes that on to :func:`parse`.
 
 Both functions return a :class:`Document` object representing the content of the
diff --git a/Doc/library/zlib.rst b/Doc/library/zlib.rst
index aea0e79..230fdfe 100644
--- a/Doc/library/zlib.rst
+++ b/Doc/library/zlib.rst
@@ -30,7 +30,7 @@
 
 .. function:: adler32(data[, value])
 
-   Computes a Adler-32 checksum of *data*.  (An Adler-32 checksum is almost as
+   Computes an Adler-32 checksum of *data*.  (An Adler-32 checksum is almost as
    reliable as a CRC32 but can be computed much more quickly.)  If *value* is
    present, it is used as the starting value of the checksum; otherwise, a fixed
    default value is used.  This allows computing a running checksum over the
diff --git a/Doc/whatsnew/2.7.rst b/Doc/whatsnew/2.7.rst
index fb0551e..3966cb4 100644
--- a/Doc/whatsnew/2.7.rst
+++ b/Doc/whatsnew/2.7.rst
@@ -1118,7 +1118,7 @@
   (Fixed by Daniel Stutzbach; :issue:`8729`.)
 
 * Constructors for the parsing classes in the :mod:`ConfigParser` module now
-  take a *allow_no_value* parameter, defaulting to false; if true,
+  take an *allow_no_value* parameter, defaulting to false; if true,
   options without values will be allowed.  For example::
 
     >>> import ConfigParser, StringIO
diff --git a/Doc/whatsnew/3.3.rst b/Doc/whatsnew/3.3.rst
index 48379d9..094eff8 100644
--- a/Doc/whatsnew/3.3.rst
+++ b/Doc/whatsnew/3.3.rst
@@ -2155,7 +2155,7 @@
   * encode an ASCII string to UTF-8 doesn't need to encode characters anymore,
     the UTF-8 representation is shared with the ASCII representation
   * the UTF-8 encoder has been optimized
-  * repeating a single ASCII letter and getting a substring of a ASCII strings
+  * repeating a single ASCII letter and getting a substring of an ASCII string
     is 4 times faster
 
 * UTF-8 is now 2x to 4x faster.  UTF-16 encoding is now up to 10x faster.