Assuming she is not otherwise inadmissible, yes, the citizen can petition his Indian wife and her children (children would be derivative beneficiaries of the mother).
If you are married in China, you do not need to return to China to file for a divorce. Canada will allow you to file for divorce and recognize the divorce that has taken place.
You go to immigration and start the paper work.
yes
Not unless you are or become a naturalized citizen of that country.
My brother married a girl from the Philippines in the Philippines. They were both previously divorced. She is a Philippine citizen. He is a US citizen. I do not know whether this will apply to your situation but it sounds similar. You might want to check with the British consulate there to be sure.
yes
yes they can but only if they are a citizen. hope that help
If they are married in Denmark...than yes
No. No one is allowed to be married to more than one person at a time in the US or Mexico.
You could A: get divorced again, this time in Greece or B: call 604 372-5492
Yes.
Because every parson has on authority