DECISION=yes

    while [ "$DECISION" = 'yes' ]; do

    echo Please, enter the users first name.
        read FNAME
    echo Please, enter the users last name.
        read LNAME
    echo Please, enter the users initial group.
        read IGROUP
    echo Please, enter any additional groups the user belongs to.
        read AGROUP

IGROUPL=`echo $IGROUP | tr [:upper:] [:lower:]`
AGROUPL=`echo $AGROUP | tr [:upper:] [:lower:]`
LNAMEU=`echo $LNAME | tr [:lower:] [:upper:]`
FNAMEU=`echo $FNAME | tr [:lower:] [:upper:]`
USRNM1=`echo $LNAME | tr [:upper:] [:lower:]`
USRNM2=`echo $FNAME | cut -c 1 | tr [:upper:] [:lower:]`
USRNM=$USRNM1$USRNM2

    useradd -c "$FNAMEU $LNAMEU" -g $IGROUPL -G $AGROUPL $USRNM
    echo 123456 | passwd $USRNM --stdin

        if getent passwd "$username" >/dev/null; then
            for i in {1..50}; do
            getent passwd "$username$i" >/dev/null || { username="$username$i; break; };
            done;
        fi

    echo "Would you like to add another user?(yes/no)"
        read YESNO
        DECISION=`echo $YESNO | tr [:upper:] [:lower:]`

    DONELOOP=1
        while [ "$DONELOOP" -eq "1" ]; do
            if [ $DECISION == 'yes' ]; then
                DECISION=yes
    DONELOOP=2
        elif [ "$DECISION" == "no" ]; then
            echo "Thank you for using this program"
    DONELOOP=2
        else
            echo "Please use a correct option.(yes/no)"
                read YESNO
            DECISION=`echo $YESNO | tr [:upper:] [:lower:]`
        fi
    done
done