How to get user's network information using Facebook Graph API? (PHP)

I have been playing with Facebook Graph API around a week, and I still could not find how to get user's network information? I don't know if the Graph API stores user's network; I didn't see such information. Simply,开发者_如何学JAVA if a user is in "Google" network, may I get the name and the ID of the networks that the user belongs to?

If this is not possible, may I reach the user's secondary email addresses?

Thanks for your help.

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Using FQL : the affiliations field of the User table contains this information

Sample call: https://graph.facebook.com/fql?q=select affiliations from user where uid= 4&access_token=<ACCESS TOKEN>

Sample response:

{
  "data": [
    {
      "affiliations": [
        {
          "nid": 16777217, 
          "name": "Harvard", 
          "type": "college"
        }, 
        {
          "nid": 50431648, 
          "name": "Facebook", 
          "type": "work"
        }
      ]
    }
  ]
}