You must have Permanent Resident (PR) status in Canada and you must be physically present in Canada for at least 1460 days i.e. 4 years out of past 6 years before the date of your application. Also, you must have lived in Canada for at least 183 days during each of four calendar years that fall within the 6 years before the date of your application. Children below 18 years do not require satisfaction of 4 years of stay condition.