diff --git a/helper.zsh b/helper.zsh
index b127bc9..89f830e 100644
--- a/helper.zsh
+++ b/helper.zsh
@@ -5,7 +5,7 @@
 #   Sorin Ionescu <sorin.ionescu@gmail.com>
 #
 
-# Checks boolean variable for "true".
+# Checks a boolean variable for "true".
 # Case insensitive: "1", "y", "yes", "t", "true", "o", and "on".
 function is-true {
   [[ -n "$1" && "$1" == (1|[Yy]([Ee][Ss]|)|[Tt]([Rr][Uu][Ee]|)|[Oo]([Nn]|)) ]]