After completed 1 year program you may get 1 year work permit
After completed 2 years program you may get 3 years work permit
After completed 1+1=2 years program you may get 2 years or 3 years work permit (some students got 2 years or 3 years)
You can do 1+1= 2 years program, and it is called combined program, for this issue you can check this link-
http://www.cic.gc.ca/english/resources/manuals/bulletins/2010/ob194A.asp
According to this link-
If you complete 1 year graduate degree, diploma or certificate from a participating institution in Canada, and do another graduate degree, diploma or certificate from a participating institution in Canada within next 2 years, you may qualify for a three-year work permit.
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