shell script case

[will@localhost ShellScript]$ cat case.sh
#!/bin/sh

case $1 in

"hello")

        echo "Hello, how are you ?"
        ;;
  "")
        echo "You MUST input parameters, ex> $0 someword"
        ;;
  *)
        echo "Usage $0 {hello}"
        ;;

esac

[will@localhost ShellScript]$