some small grammatical corrections

Author: barriesegal

draft/faq/storage.txt

@@ -18,7 +18,7 @@ the :doc:`complete list of FAQs </faq>` or post your question to the
 What are memory mapped files?
 -----------------------------
 
-Memory mapped files are segments are a way of keeping files and data
+Memory mapped files are a way of keeping files and data
 up to date in memory using the system call ``mmap()``. MongoDB uses
 memory mapped files as its storage engine. By using memory mapped
 files MongoDB can treat the content of its data files as if they were
@@ -30,7 +30,7 @@ How do memory mapped files work?
 
 Memory mapping assigns files to a block of virtual memory with a
 direct byte-for-byte correlation. Once mapped, the relationship
-between file and memory, allows MongoDB to interact with the data in
+between file and memory allows MongoDB to interact with the data in
 the file as if it were memory.
 
 How does MongoDB work with memory mapped files?
@@ -55,9 +55,9 @@ What is the difference between soft and hard page faults?
 ---------------------------------------------------------
 
 :term:`Page faults <page fault>` occur when MongoDB needs access to
-data that isn't currently in active memory. A "hard" page fault,
+data that isn't currently in active memory. A "hard" page fault
 refers to situations when MongoDB must access a disk to access the
-data. A "soft" page fault, by contrast merely moves memory pages from
+data. A "soft" page fault, by contrast, merely moves memory pages from
 one list to another, and does not require as much time to complete.
 
 What tools can I use to investigate storage use in MongoDB?
@@ -73,11 +73,11 @@ What is the working set?
 
 Working set represents the total body of data that the application
 uses in the course of normal operation. Often this is a subset of the
-total data size, but the specific size of working set depends on
+total data size, but the specific size of the working set depends on
 actual moment-to-moment use of the database.
 
 If you run a query that requires MongoDB to scan every
-:term:`document` in a collection, the working set includes every
+:term:`document` in a collection, the working set includes every active
 document in memory.
 
 For best performance, the majority of your *active* set should fit in