试着回答一下

来源: 于 2008-07-20 05:07:45 [旧帖] [给我悄悄话] 本文已被阅读：次

knock, knock...
"who's there?"
"ya"
"ya who?"
"yahoo"
"i don't know you."

so, as you can see, you heard the voice but you can not get in. why?