Common Law/Conjugal Partners?

So, I was thinking about sponsoring my boyfriend, drom the Dominican Republic to come to Canada. We've been surrounded by a relationship for more than 3 years now, and think it would be time to start our lives together, yet we don't want to get hold of married yet! So I was wondering, what would be our best option? Common tenet or Conjugal partners? If I would do common law, I would be moving in attendance very soon, and live with him for about 2 years so that we would be capable of prove we've lived together. But I heard that if we wanted to go for Conjugal partner, we had to prove we weren't able to move in together or something??.. Is academy a good enough reason? Is anyone used to with this process, as I am feeling completely lost and hopeless!
Answers:   
http://www.cic.gc.ca/english/immigrate/s...


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