diff --git a/opt/cs50/lib/help50/bash b/opt/cs50/lib/help50/bash
index de1198c..6c298b0 100755
--- a/opt/cs50/lib/help50/bash
+++ b/opt/cs50/lib/help50/bash
@@ -12,6 +12,11 @@ if [[ "$output" =~ $regex ]]; then
     fi
 fi
 
+regex="bash: \./(.*): Is a directory"
+if [[ "$output" =~ $regex ]]; then
+    echo "Cannot execute a directory. Did you mean to \`cd\` into \`${BASH_REMATCH[1]}\` instead?"
+fi
+
 regex="bash: (./.*\.py): Permission denied"
 if [[ "$output" =~ $regex ]]; then