求大佬帮忙看看脚本那边错了，提示loop缺少do，求帮助

# $language = "VBScript"
# $interface = "1.0"
Sub Main
Const ForReading = 1, ForWriting = 2, ForAppending = 8
Dim fso,file1,line,str1,str2,str3,str4,params
Set fso = CreateObject("Scripting.FileSystemObject")
Set file1 = fso.OpenTextFile("D:\Scripts\ip.txt",Forreading, False)
crt.Screen.Synchronous = True
DO While file1.AtEndOfStream <> True
line = file1.ReadLine
params = Split (line)
crt.session.LogFileName = "d:\backup\log\2019.11\" & params(0) & ".txt"
crt.session.Log(true)
crt.Session.Connect "/TELNET " & params(0)
wordkey1 = crt.Screen.WaitForStrings ("username:","login:","Username:",3)
Select case wordkey1
case 1
crt.Screen.Send params(1) & vbcr
wordkey2 = crt.Screen.WaitForStrings ("Password:","PASSWORD:","PASSCODE:",3)
Select case wordkey2
case 2
crt.Screen.Send params(2) & vbcr
crt.Screen.waitForString " ",3
str1 = " "
crt.Screen.Send vbcr
str2 = str1 & params(0) & ".cfg"
str3 = "tftp 172.17.189.190 put startup.cfg "
str4 = str3 & str2
crt.Screen.Send str4 & vbcr
crt.Screen.WaitForString "Press CTRL+C to abort."
crt.Session.Disconnect
loop
crt.Screen.Synchronous = False
End Sub