diff --git a/sudo.md b/sudo.md
index 8ff5cdc..fbb8c70 100644
--- a/sudo.md
+++ b/sudo.md
@@ -18,7 +18,7 @@ acme.sh --uninstall
 sudo su
 
 #install again for root user
-curl https://get.acme.sh | sh
+curl https://get.acme.sh | sh -s email=my@example.com
 
 #use it
 bash