diff --git a/thefuck/rules/upper_to_lower_case.py b/thefuck/rules/upper_to_lower_case.py
index 5f91b01b..afdad5dd 100644
--- a/thefuck/rules/upper_to_lower_case.py
+++ b/thefuck/rules/upper_to_lower_case.py
@@ -1,6 +1,10 @@
 from thefuck.utils import get_all_executables, which
 
-
+# this rule is activated when the typed command is
+# in uppercase letters and if the command is not 
+# executed. However in order to activate this rule
+# it is necessary the first word of the whole command
+# to be valid.
 def match(command):
     return (command.script.isupper()
     	    and not which(command.script_parts[0])
@@ -8,7 +12,7 @@ def match(command):
                  or 'is not recognized as' in command.output)
             and (command.script_parts[0].lower() in get_all_executables()))
 
-
+# returns the same command in lowercase letters
 def get_new_command(cmd):
     return cmd.script.lower()