为什么能执行却不能创建用户？

#!/bin/bsah
#批量添加指定数量的用户
read -p "Please input user name: " -t 30 name
read -p "Please input the number of users: " -t 30 num
read -p "Please input the password of users: " -t 30 pass
   if [ ! -z "$name" -a ! -z "$num" -a ! -z "$pass" ]
         then
         y=$(echo $num | sed 's/[0-9]//g')
        if [ -z "$y" ]
        then
        for (( i=1;i<$num;i=i+1 ))
         do
        /usr/sbin/useradd $name$i &>/dev/null
        echo $pass | /usr/bin/passwd --stdin $name$i &>/dev/null
        done
     fi

fi

我照着视频写的，为什么我的创建不了用户啊？