diff --git a/bash/bash9.sh b/bash/bash9.sh
index fc7d6a0..3973a03 100644
--- a/bash/bash9.sh
+++ b/bash/bash9.sh
@@ -1 +1,4 @@
-# write a loop to replace spaces to underscores in all file names in the current directory
+for file in *; do
+	echo "${file// /_}"
+	mv "$file" "${file// /_}"
+done