Try,

 #!/bin/bash
 pause ()
 {
 REPLY=Y
 while [ "$REPLY" == "Y" ] || [ "$REPLY" != "y" ]
 do
 echo -e "\t\tPress 'y' to continue\t\t\tPress 'n' to quit"
 read -n1 -s
 case "$REPLY" in
 "n") exit ;;
 "N") echo "case sensitive!!" ;; 
 "y") clear ;;
 "Y") echo "case sensitive!!" ;;
 * ) echo "Invalid Option" ;;
 esac
 done
 }
 pause
 echo "Hi"