doc: Fix some grammar

This is an extraction of the user-visible changes done in 410aa24,
including all the relevant documentation parts.

Author: Justin Pryzby
Discussion: https://postgr.es/m/20220124030001.GQ23027@telsasoft.com
Backpatch-through: 10

doc/src/sgml/config.sgml

@@ -8208,8 +8208,8 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
         This parameter specifies the default table access method to use when
         creating tables or materialized views if the <command>CREATE</command>
         command does not explicitly specify an access method, or when
-        <command>SELECT ... INTO</command> is used, which does not allow to
-        specify a table access method. The default is <literal>heap</literal>.
+        <command>SELECT ... INTO</command> is used, which does not allow
+        specifying a table access method. The default is <literal>heap</literal>.
        </para>
       </listitem>
      </varlistentry>

doc/src/sgml/ddl.sgml

@@ -3986,7 +3986,7 @@ ALTER TABLE measurement ATTACH PARTITION measurement_y2008m02
      holding an <literal>ACCESS EXCLUSIVE</literal> lock on that partition.
      It is recommended to drop the now-redundant <literal>CHECK</literal>
      constraint after the <command>ATTACH PARTITION</command> is complete.  If
-     the table being attached is itself a partitioned table then each of its
+     the table being attached is itself a partitioned table, then each of its
      sub-partitions will be recursively locked and scanned until either a
      suitable <literal>CHECK</literal> constraint is encountered or the leaf
      partitions are reached.
@@ -4001,7 +4001,7 @@ ALTER TABLE measurement ATTACH PARTITION measurement_y2008m02
      the partition being attached.  This operation will be performed whilst
      holding an <literal>ACCESS EXCLUSIVE</literal> lock on the <literal>
      DEFAULT</literal> partition.  If the <literal>DEFAULT</literal> partition
-     is itself a partitioned table then each of its partitions will be
+     is itself a partitioned table, then each of its partitions will be
      recursively checked in the same way as the table being attached, as
      mentioned above.
     </para>

doc/src/sgml/perform.sgml

@@ -1337,7 +1337,7 @@ nd | {"1, 2": 33178, "1, 5": 33178, "2, 5": 27435, "1, 2, 5": 33178}
     <title>Multivariate MCV Lists</title>
 
     <para>
-     Another type of statistics stored for each column are most-common value
+     Another type of statistic stored for each column are most-common value
      lists.  This allows very accurate estimates for individual columns, but
      may result in significant misestimates for queries with conditions on
      multiple columns.

doc/src/sgml/protocol.sgml

@@ -2078,7 +2078,7 @@ The commands accepted in replication mode are:
       streaming starts on timeline <replaceable class="parameter">tli</replaceable>;
       otherwise, the server's current timeline is selected. The server can
       reply with an error, for example if the requested section of WAL has already
-      been recycled. On success, server responds with a CopyBothResponse
+      been recycled. On success, the server responds with a CopyBothResponse
       message, and then starts to stream WAL to the frontend.
      </para>
 

doc/src/sgml/ref/pg_receivewal.sgml

@@ -82,9 +82,8 @@ PostgreSQL documentation
     <listitem>
      <para>
       First, scan the directory where the WAL segment files are written and
-      find the newest completed segment file, using as starting point the
-      beginning of the next WAL segment file. This is calculated independently
-      on the compression method used to compress each segment.
+      find the newest completed segment file, using as the starting point the
+      beginning of the next WAL segment file.
      </para>
     </listitem>
 
@@ -92,7 +91,7 @@ PostgreSQL documentation
      <para>
       If a starting point cannot be calculated with the previous method,
       the latest WAL flush location is used as reported by the server from
-      a <literal>IDENTIFY_SYSTEM</literal> command.
+      an <literal>IDENTIFY_SYSTEM</literal> command.
      </para>
     </listitem>
    </orderedlist>

doc/src/sgml/ref/select_into.sgml

@@ -107,7 +107,7 @@ SELECT [ ALL | DISTINCT [ ON ( <replaceable class="parameter">expression</replac
 
   <para>
    In contrast to <command>CREATE TABLE AS</command>, <command>SELECT
-   INTO</command> does not allow to specify properties like a table's access
+   INTO</command> does not allow specifying properties like a table's access
    method with <xref linkend="sql-createtable-method" /> or the table's
    tablespace with <xref linkend="sql-createtable-tablespace" />. Use
    <command>CREATE TABLE AS</command> if necessary.  Therefore, the default table