DOC: bug fixes in vops docs

Author: Liudmila Mantrova

doc/src/sgml/vops.sgml

@@ -24,7 +24,7 @@
     For query types other than filtering and aggregation,
     <filename>vops</filename> can also use <filename>postgres_fdw</filename>
     to present vectorized data as a regular table with scalar
-    column types and process these queries as regular tuples.
+    column types and process this data as regular tuples.
   </para>
 
 <sect2>
@@ -566,7 +566,7 @@ WHERE filter(l_shipdate &lt;= '1998-12-01'::date);
       columns. The <filename>vops</filename> extension supports grouping only by an integer type.
       The <literal>map</literal> function accepts aggregation
       arguments as a variadic array, so all elements of this array should
-      have the same type. You cannot calculate
+      have the same type. For example, you cannot calculate
       aggregates for <literal>vops_float4</literal> and
       <literal>vops_int8</literal> columns in a single operation.
     </para>
@@ -592,7 +592,7 @@ WHERE filter(l_shipdate &lt;= '1998-12-01'::date);
       Alternatively, you can partition the vectorized table by the
       <command>GROUP BY</command> fields to calculate grouped aggregates.
       In this case, grouping keys are stored as regular scalar values,
-      while other fields are  be  way and other fields - inside tiles. Now
+      while other fields are stored inside tiles. Now
       &project; executor will execute vops aggregates for each group:
     </para>
     <programlisting>