对于加拿大永久居民（移民）的居住义务，官方网站的说明：
OBLIGATIONS

Permanent residents comply with residency obligations if they accumulate two years of physical presence in Canada in every five-year period. If they are outside of Canada for extended periods of time, they can accumulate residency days if they are:
accompanying a Canadian spouse or common-law partner, or are a child accompanying a parent; employed on a full-time basis by a Canadian business or the Public Service of Canada; or the accompanying spouse, common-law partner or child of a permanent resident who is outside Canada and who is employed on a full-time basis by a Canadian business or the Public Service of Canada.
Under the transitional provisions, a permanent resident in possession of a Returning Resident Permit will be able to count time spent outside Canada for the purpose of satisfying residency obligations.

When making residency decisions, officers can take into account humanitarian and compassionate concerns. Officers will consider the best interests of a child who would be affected by the decision.

The assessment of residency obligations for a person who has been a permanent resident for more than five years, will be limited to the five years immediately preceding the examination.


1．五年住满两年的规定的理解
一个永久居民，在任何一个五年时间以内，必须有两年的时间居住在加拿大。
这两年得时间是如何计算的呢，有以下几种情况：
1) 本人在加拿大居住（只是居住，没有其他额外要求）；
2) 陪伴有加拿大国籍的配偶或父母在海外居住的时间也可以算在内。(注意，在海外陪伴有加拿大国籍的子女则不能算)；
3) 为一家驻外的加拿大公司或加拿大政府机构全职雇佣。
4) 陪伴一个为一家驻外的加拿大公司或加拿大政府机构全职雇佣的具有永久居民身份的配偶或子女（该永久居民也要符合上述5年内住满2年的要求）。

2．如何计算五年的时间？
五年的时间段从移民登陆之日算起。也就是说从你在国外打算再次登陆加拿大时，倒数回去五年。只要您能证明在这个五年段的时间里，您通过以上所说的三种办法之一，满足住满两年的要求，就没有问题了。

注意：
坐移民监，满足五年住满两年的要求，不是主申请人才有的义务，也不是家庭成员才有的义务。是每一个永久居民都有的义务。所以，是不能代替的。谁住满了，谁就维持住身份。谁没有住满，谁就丧失身份。不能替代。也不能由一家出一个代表完成。
五年中不住满两年，移民身份可能丧失

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