group field tags
diff --git a/flags.go b/flags.go
index ef81991..d22e44a 100644
--- a/flags.go
+++ b/flags.go
@@ -60,9 +60,13 @@
// and Unmarshaler interfaces.
//
// Available field tags:
-// short: the short name of the option (single character)
-// long: the long name of the option
-// description: the description of the option (optional)
+// short: the short name of the option (single character)
+// long: the long name of the option
+// required: whether an option is required to appear on the command line.
+// If a required option is not present, the parser will return
+// ErrRequired.
+// description: the description of the option (optional)
+//
// optional: whether an argument of the option is optional (optional)
// optional-value: the value of an optional option when the option occurs
// without an argument. This tag can be specified multiple
@@ -75,18 +79,16 @@
// showing up in the help. If default-mask takes the special
// value "-", then no default value will be shown at all
// (optional)
-// required: whether an option is required to appear on the command
-// line. If a required option is not present, the parser
-// will return ErrRequired.
-// base: a base (radix) used to convert strings to integer values,
-// the default base is 10 (i.e. decimal) (optional)
// value-name: the name of the argument value (to be shown in the help,
// (optional)
-// group: when specified on a struct field, makes the struct field
-// a separate group with the given name (optional).
-// command: when specified on a struct field, makes the struct field
-// a (sub)command with the given name (optional).
//
+// base: a base (radix) used to convert strings to integer values, the default
+// base is 10 (i.e. decimal) (optional)
+//
+// group: when specified on a struct field, makes the struct
+// field a separate group with the given name (optional).
+// command: when specified on a struct field, makes the struct
+// field a (sub)command with the given name (optional).
// subcommands-optional: when specified on a command struct field, makes
// any subcommands of that command optional.
//
