diff --git a/man2/perf_event_open.2 b/man2/perf_event_open.2
index 5900b1cb6..9d2004b12 100644
--- a/man2/perf_event_open.2
+++ b/man2/perf_event_open.2
@@ -24,7 +24,7 @@
 .\" This document is based on the perf_event.h header file, the
 .\" tools/perf/design.txt file, and a lot of bitter experience.
 .\"
-.TH PERF_EVENT_OPEN 2 2013-06-21 "Linux" "Linux Programmer's Manual"
+.TH PERF_EVENT_OPEN 2 2013-07-02 "Linux" "Linux Programmer's Manual"
 .SH NAME
 perf_event_open \- set up performance monitoring
 .SH SYNOPSIS
@@ -1666,7 +1666,7 @@ file descriptor argument.
 
 If the 
 .B PERF_IOC_FLAG_GROUP
-bit is set in the ioctl argument then all events in a group are 
+bit is set in the ioctl argument, then all events in a group are 
 enabled, even if the event specified is not the group leader.
 .TP
 .B PERF_EVENT_IOC_DISABLE
@@ -1682,7 +1682,7 @@ stops that counter from counting but doesn't affect any other counter.
 
 If the 
 .B PERF_IOC_FLAG_GROUP
-bit is set in the ioctl argument then all events in a group are 
+bit is set in the ioctl argument, then all events in a group are 
 disabled, even if the event specified is not the group leader.
 .TP
 .B PERF_EVENT_IOC_REFRESH
@@ -1711,12 +1711,12 @@ values.
 
 If the 
 .B PERF_IOC_FLAG_GROUP
-bit is set in the ioctl argument then all events in a group are 
+bit is set in the ioctl argument, then all events in a group are 
 reset, even if the event specified is not the group leader.
 
 If the
 .B PERF_IOC_FLAG_GROUP
-bit is not set then the behavior is somwhat unexpected:
+bit is not set, then the behavior is somwhat unexpected:
 when sent to a group leader only the leader is reset 
 (children are left alone); 
 when sent to a child all events in a group are reset.