全国高职学校排名:ASP运行过程中的“缺少对象: ''”问题

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dim id,name,sex,chamber,phone_number,qq,mobile_phone,intro,db,str,rs
id=trim(request.form("ID"))
name=trim(request.form("name"))
sex=trim(request.form("sex"))
chamber=trim(request.form("chamber"))
phone_number=clng(request.form("phone_number"))
qq=trim(request.form("QQ"))
mobile_phone=trim(request.form("mobile_phone"))
intro=trim(request.form("intro"))
if id<>"" and name<>"" and sex<>"" and chamber<>"" then
set db=server.createobject("ADODB.connection")
db.open "Dsn=class_data"
str="select * from classmate where student_ID='"&id&"' and classmate_name='"&name&"' and sex='"&sex&"'"
set rs=db.execute(str)
if not rs.bof and not rs.eof then
response.write "<p><font color='red'>记录已存在！</p>"
response.end
else
str="insert into classmate (student_ID,classmate_name,sex,chamber_number,chamber_phone,QQ,mobile_phone,number_intro)

values('"&id&"','"&name&"','"&sex&"','"&chamber&"',"&phone_number&",'"&qq&"','"&mobile_phone&"','"&intro&"')"
db.execute(str)
response.write "<script language='javascript'>"
response.write "alert('添加成功！');"
response.write "</script>"
end if
end if
rs.close
set rs=nothing
db.close
set db=nothing
=================================================================
运行时提示
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Microsoft VBScript 运行时错误 (0x800A01A8)
缺少对象: ''
/class_data/insert.asp, 第 55 行
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也就是第一个end if那句,请问这是怎么回事？
谢谢!
注：
str="insert into classmate (student_ID,classmate_name,sex,chamber_number,chamber_phone,QQ,mobile_phone,number_intro)

values('"&id&"','"&name&"','"&sex&"','"&chamber&"',"&phone_number&",'"&qq&"','"&mobile_phone&"','"&intro&"')"
中没有换行，是输入错误！