First of all, I don't have experience on this, but I don't think you can sponse them at the same time - you have an intension to immigrate... Maybe one or two persons at a time.
Thanks a lot. It's such good news to me, I'll try. I have enough revenue and also they have saving and own property, but I worry about if I invite them all at the same time,the Consulate Canada will think they have immigration tendency.