diff --git a/subjects/ztail/README.md b/subjects/ztail/README.md
index 8af7a98c..80a94962 100644
--- a/subjects/ztail/README.md
+++ b/subjects/ztail/README.md
@@ -25,7 +25,7 @@ abcdefghijklmnopqrstuvwxyz
 
 Normal cases :
 
-```
+```console
 $ go run . -c 4 file1.txt
 xyz
 $ go run . -c 4 file1.txt file2.txt
@@ -39,7 +39,7 @@ $
 
 Error cases :
 
-```
+```console
 $ go run . -c 4 file1.txt nonexisting1.txt file2.txt nonexisting2.txt
 ==> file1.txt <==
 xyz