diff --git a/doc/src/sgml/parallel.sgml b/doc/src/sgml/parallel.sgml
index 3e8326d46c..2b2c8cbffd 100644
--- a/doc/src/sgml/parallel.sgml
+++ b/doc/src/sgml/parallel.sgml
@@ -128,7 +128,7 @@ EXPLAIN SELECT * FROM pgbench_accounts WHERE filler LIKE '%x%';
 
   <para>
     In addition, the system must not be running in single-user mode.  Since
-    the entire database system is running in single process in this situation,
+    the entire database system is running as a single process in this situation,
     no background workers will be available.
   </para>
 
diff --git a/doc/src/sgml/ref/alter_table.sgml b/doc/src/sgml/ref/alter_table.sgml
index 8933bb0d77..6292c4774a 100644
--- a/doc/src/sgml/ref/alter_table.sgml
+++ b/doc/src/sgml/ref/alter_table.sgml
@@ -975,7 +975,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
       constraint. This does not work, however, if any of the partition keys
       is an expression and the partition does not accept
       <literal>NULL</literal> values. If attaching a list partition that will
-      not accept <literal>NULL</literal> values, also add
+      not accept <literal>NULL</literal> values, also add a
       <literal>NOT NULL</literal> constraint to the partition key column,
       unless it's an expression.
      </para>
diff --git a/doc/src/sgml/sources.sgml b/doc/src/sgml/sources.sgml
index e6ae02f2af..4ee99853b2 100644
--- a/doc/src/sgml/sources.sgml
+++ b/doc/src/sgml/sources.sgml
@@ -929,8 +929,8 @@ BETTER: unrecognized node type: 42
    <simplesect>
     <title>Function-Like Macros and Inline Functions</title>
     <para>
-     Both, macros with arguments and <literal>static inline</literal>
-     functions, may be used. The latter are preferable if there are
+     Both macros with arguments and <literal>static inline</literal>
+     functions may be used. The latter are preferable if there are
      multiple-evaluation hazards when written as a macro, as e.g., the
      case with
 <programlisting>
diff --git a/src/backend/access/common/bufmask.c b/src/backend/access/common/bufmask.c
index 003a0befb2..409acecf42 100644
--- a/src/backend/access/common/bufmask.c
+++ b/src/backend/access/common/bufmask.c
@@ -78,7 +78,7 @@ mask_unused_space(Page page)
 	if (pd_lower > pd_upper || pd_special < pd_upper ||
 		pd_lower < SizeOfPageHeaderData || pd_special > BLCKSZ)
 	{
-		elog(ERROR, "invalid page pd_lower %u pd_upper %u pd_special %u\n",
+		elog(ERROR, "invalid page pd_lower %u pd_upper %u pd_special %u",
 			 pd_lower, pd_upper, pd_special);
 	}
 
diff --git a/src/backend/access/spgist/spgutils.c b/src/backend/access/spgist/spgutils.c
index 4484805192..a76c52aa94 100644
--- a/src/backend/access/spgist/spgutils.c
+++ b/src/backend/access/spgist/spgutils.c
@@ -1302,7 +1302,7 @@ spgproperty(Oid index_oid, int attno,
 	/*
 	 * Currently, SP-GiST distance-ordered scans require that there be a
 	 * distance operator in the opclass with the default types. So we assume
-	 * that if such a operator exists, then there's a reason for it.
+	 * that if such an operator exists, then there's a reason for it.
 	 */
 
 	/* First we need to know the column's opclass. */
diff --git a/src/backend/jit/llvm/llvmjit.c b/src/backend/jit/llvm/llvmjit.c
index 199fff4f77..e8eb83ebd3 100644
--- a/src/backend/jit/llvm/llvmjit.c
+++ b/src/backend/jit/llvm/llvmjit.c
@@ -816,7 +816,7 @@ llvm_session_initialize(void)
 
 	if (LLVMGetTargetFromTriple(llvm_triple, &llvm_targetref, &error) != 0)
 	{
-		elog(FATAL, "failed to query triple %s\n", error);
+		elog(FATAL, "failed to query triple %s", error);
 	}
 
 	/*
diff --git a/src/backend/optimizer/util/tlist.c b/src/backend/optimizer/util/tlist.c
index 1ba13be59f..98f008bac8 100644
--- a/src/backend/optimizer/util/tlist.c
+++ b/src/backend/optimizer/util/tlist.c
@@ -865,7 +865,7 @@ apply_pathtarget_labeling_to_tlist(List *tlist, PathTarget *target)
  *
  * The outputs of this function are two parallel lists, one a list of
  * PathTargets and the other an integer list of bool flags indicating
- * whether the corresponding PathTarget contains any evaluatable SRFs.
+ * whether the corresponding PathTarget contains any evaluable SRFs.
  * The lists are given in the order they'd need to be evaluated in, with
  * the "lowest" PathTarget first.  So the last list entry is always the
  * originally given PathTarget, and any entries before it indicate evaluation
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index b4eb4e18e6..7c8b4db7e6 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -11315,7 +11315,7 @@ get_opclass_name(Oid opclass, Oid actual_datatype,
 
 /*
  * generate_opclass_name
- *		Compute the name to display for a opclass specified by OID
+ *		Compute the name to display for an opclass specified by OID
  *
  * The result includes all necessary quoting and schema-prefixing.
  */
diff --git a/src/bin/pg_upgrade/info.c b/src/bin/pg_upgrade/info.c
index 5d9a26cf82..7ecbd55670 100644
--- a/src/bin/pg_upgrade/info.c
+++ b/src/bin/pg_upgrade/info.c
@@ -431,11 +431,10 @@ get_rel_infos(ClusterInfo *cluster, DbInfo *dbinfo)
 	query[0] = '\0';			/* initialize query string to empty */
 
 	/*
-	 * Create a CTE that collects OIDs of regular user tables, including
-	 * matviews and sequences, but excluding toast tables and indexes.  We
-	 * assume that relations with OIDs >= FirstNormalObjectId belong to the
-	 * user.  (That's probably redundant with the namespace-name exclusions,
-	 * but let's be safe.)
+	 * Create a CTE that collects OIDs of regular user tables and matviews,
+	 * but excluding toast tables and indexes.  We assume that relations with
+	 * OIDs >= FirstNormalObjectId belong to the user.  (That's probably
+	 * redundant with the namespace-name exclusions, but let's be safe.)
 	 *
 	 * pg_largeobject contains user data that does not appear in pg_dump
 	 * output, so we have to copy that system table.  It's easiest to do that
diff --git a/src/test/regress/expected/expressions.out b/src/test/regress/expected/expressions.out
index 9699d86cc6..6b0ac8e1f9 100644
--- a/src/test/regress/expected/expressions.out
+++ b/src/test/regress/expected/expressions.out
@@ -57,7 +57,7 @@ SELECT now()::timestamp::text = localtimestamp::text;
  t
 (1 row)
 
--- current_role/user/user is tested in rolnames.sql
+-- current_role/user/user is tested in rolenames.sql
 -- current database / catalog
 SELECT current_catalog = current_database();
  ?column? 
diff --git a/src/test/regress/sql/expressions.sql b/src/test/regress/sql/expressions.sql
index f9f9f97efa..f87751f4ef 100644
--- a/src/test/regress/sql/expressions.sql
+++ b/src/test/regress/sql/expressions.sql
@@ -24,7 +24,7 @@ SELECT length(current_timestamp::text) >= length(current_timestamp(0)::text);
 -- localtimestamp
 SELECT now()::timestamp::text = localtimestamp::text;
 
--- current_role/user/user is tested in rolnames.sql
+-- current_role/user/user is tested in rolenames.sql
 
 -- current database / catalog
 SELECT current_catalog = current_database();