diff --git a/subjects/cat.en.md b/subjects/cat.en.md
index 03a923b14..8e5875d36 100644
--- a/subjects/cat.en.md
+++ b/subjects/cat.en.md
@@ -18,17 +18,21 @@ Write a program that has the same behaviour as the system's `cat` command-line.
 
 `"Alan Mathison Turing was an English mathematician, computer scientist, logician, cryptanalyst. Turing was highly influential in the development of theoretical computer science, providing a formalisation of the concepts of algorithm and computation with the Turing machine, which can be considered a model of a general-purpose computer. Turing is widely considered to be the father of theoretical computer science and artificial intelligence."`
 
+-   In case of error the program should print the error.
+
 -   The program must be submitted inside a folder named `cat`.
 
 ```console
 student@ubuntu:~/piscine-go/cat$ go build
-student@ubuntu:~/piscine-go/cat$ ./cat Hello There
-Hello
-There
+student@ubuntu:~/piscine-go/cat$ ./cat abc
+open abc: no such file or directory
 student@ubuntu:~/piscine-go/cat$ ./cat quest8.txt
 "Programming is a skill best acquired by pratice and example rather than from books" by Alan Turing
+student@ubuntu:~/piscine-go/cat$ ./cat
+Hello
+Hello^C
 student@ubuntu:~/piscine-go/cat$ ./cat quest8.txt quest8T.txt
 "Programming is a skill best acquired by pratice and example rather than from books" by Alan Turing
-
 "Alan Mathison Turing was an English mathematician, computer scientist, logician, cryptanalyst. Turing was highly influential in the development of theoretical computer science, providing a formalisation of the concepts of algorithm and computation with the Turing machine, which can be considered a model of a general-purpose computer. Turing is widely considered to be the father of theoretical computer science and artificial intelligence."
+student@ubuntu:~/piscine-go/cat$
 ```