diff --git a/nodebrew b/nodebrew
index a0beac3..0b05b2e 100755
--- a/nodebrew
+++ b/nodebrew
@@ -210,7 +210,7 @@ sub _cmd_alias {
     # get alias
     elsif ($key) {
         $val = $alias->get($key);
-        print "$key -> $val";
+        print $val ? "$key -> $val\n" : "$key is not set alias\n";
     }
     # get alias all
     else {
@@ -306,7 +306,7 @@ Usage:
     nodebrew help                    Show this message
     nodebrew install <version>       Download and install a <version>
     nodebrew uninstall <version>     Uninstall a version
-    nodebrew use <version>           Modify PATH to use <version>
+    nodebrew use <version>           Use <version>
     nodebrew list                    List installed versions
     nodebrew ls                      Alias for `list`
     nodebrew ls-remote               List remote versions
diff --git a/t/command.t b/t/command.t
index b60534b..9d329e6 100644
--- a/t/command.t
+++ b/t/command.t
@@ -203,6 +203,9 @@ sub run_test {
     is $run->('alias', ['foo', 'baz']), "foo -> baz\n";
     is $run->('alias'), "foo -> baz\nhoge -> fuga\n";
 
+    is $run->('alias', ['baz']), "baz is not set alias\n";
+    is $run->('alias', ['foo']), "foo -> baz\n";
+
     $run->('alias', ['foo', 'v0.6.0']);
     $run->('use', ['foo']);
     like $run->('list'), qr/current: v0.6.0/;