grammar and readability

corrected verb agreement ("are still require" -> "still require") and adjusted punctuation to improve sentence division and readability

Author: RubyTuesdayDONO

source/core/read-operations.txt

@@ -872,9 +872,8 @@ Aggregation
 
 MongoDB can perform some basic data aggregation operations on results
 before returning data to the application. These operations are not
-queries, they use :term:`database commands <database command>` rather than queries, and
-they do not return a cursor; however, they are still require MongoDB
-to read data.
+queries; they use :term:`database commands <database command>` rather than queries, and
+they do not return a cursor. However, they still require MongoDB to read data.
 
 Running aggregation operations on the database side can be more
 efficient than running them in the application layer and can reduce