expect脚本问题

Question

`#!/usr/bin/expect -f
set timeout 3
spawn ssh root@192.168.1.1
expect "password: "
send "root\r"
expect "#"
send "su - root\r"
expect "*password："
send "root\r"
interact`

上面的脚本执行到最后自动退出
是不是脚本语法有问题呢？