can a Brit who emigrated to Canada in 2005 gain dual citizenship?

Posted September 15th, 2011 by immigratecanada and filed in Immigration to Canada

without losing the right to live back in England?
we thought it would make us more “flexible” with living in UK or Canada also we can sponsor direct family in to Canada if we become Canadian citizens

my question is, do we have to give up our Brit citizenship or can we have both citizenships