followup to #37284 with additional feedback

Author: bleskes

docs/reference/docs/concurrency-control.asciidoc

@@ -14,8 +14,8 @@ operation performed to a document is assigned a sequence number by the primary
 shard that coordinates that change. The sequence number is increased with each
 operation and thus newer operations are guaranteed to have a higher sequence
 number than older operations. Elasticsearch can then use the sequence number of
-operations to make sure they never override a newer document version is never
-overridden by a change that has a smaller sequence number assigned to it.
+operations to make sure a newer document version is never overridden by
+a change that has a smaller sequence number assigned to it.
 
 For example, the following indexing command will create a document and assign it
 an initial sequence number and primary term:

docs/reference/docs/index_.asciidoc

@@ -341,13 +341,13 @@ then the operation is executed without any version checks.
 
 The above will succeed since the the supplied version of 2 is higher than
 the current document version of 1. If the document was already updated
-and it's version was set to 2 or higher, the indexing command will fail
+and its version was set to 2 or higher, the indexing command will fail
 and result in a conflict (409 http status code).
 
 WARNING: External versioning supports the value 0 as a valid version number.
 This allows the version to be in sync with an external versioning system
 where version numbers start from zero instead of one. It has the side effect
-that documents with version number equal to zero cannot neither be updated
+that documents with version number equal to zero can neither be updated
 using the <<docs-update-by-query,Update-By-Query API>> nor be deleted
 using the <<docs-delete-by-query,Delete By Query API>> as long as their
 version number is equal to zero.
@@ -357,7 +357,7 @@ of async indexing operations executed as a result of changes to a source
 database, as long as version numbers from the source database are used.
 Even the simple case of updating the Elasticsearch index using data from
 a database is simplified if external versioning is used, as only the
-latest version will be used if the index operations are out of order for
+latest version will be used if the index operations arrive out of order for
 whatever reason.
 
 [float]