diff --git a/number_generator.pl b/number_generator.pl
index b706fe4..bedc03d 100644
--- a/number_generator.pl
+++ b/number_generator.pl
@@ -42,14 +42,14 @@ sub generate_number_without_uppercase_and_end_marks($number) {
     # This is done in this way attempting to split the big problem
     # in many smaller problems.
     append_millions_to_return(\$number, \$return);
-    my $there_is_hundred_thousands = append_thousand_hundreds(\$number, \$return);
-    append_decene_thousands(\$number, \$return, $there_is_hundred_thousands);
-    append_hundred(\$number, \$return);
-    append_decene(\$number, \$return); 
+    my $there_is_hundred_thousands = append_thousand_hundreds_to_return(\$number, \$return);
+    append_decene_thousands_to_return(\$number, \$return, $there_is_hundred_thousands);
+    append_hundred_to_return(\$number, \$return);
+    append_decene_to_return(\$number, \$return); 
     return $return;
 }
 
-sub append_decene($number_ref, $return_ref) {
+sub append_decene_to_return($number_ref, $return_ref) {
     my $number = ${$number_ref};
     my $decene = int ($number / 1);
     return if ($decene < 1);
@@ -58,7 +58,7 @@ sub append_decene($number_ref, $return_ref) {
     ${$number_ref} = 0;
 }
 
-sub append_decene_thousands($number_ref, $return_ref, $there_is_hundred_thousands) {
+sub append_decene_thousands_to_return($number_ref, $return_ref, $there_is_hundred_thousands) {
     my $number = ${$number_ref};
     my $thousand_decene_unit = int ($number / 1_000);
     # This is needed for numbers such as 1_100_001 that do not have thousand decenes
@@ -72,7 +72,7 @@ sub append_decene_thousands($number_ref, $return_ref, $there_is_hundred_thousand
     ${$number_ref} = $number % 1_000;
 }
 
-sub append_hundred($number_ref, $return_ref) {
+sub append_hundred_to_return($number_ref, $return_ref) {
     my $number = ${$number_ref};
     my $hundred = int ($number / 100);
     return if ($hundred < 1);
@@ -100,7 +100,7 @@ sub convert_two_chars_number_to_words($number) {
     return $return;
 }
 
-sub append_thousand_hundreds($number_ref, $return_ref) {
+sub append_thousand_hundreds_to_return($number_ref, $return_ref) {
     my $number = ${$number_ref};
     my $thousand_hundreds_unit = int ($number / 100_000);
     return if ($thousand_hundreds_unit < 1);