またはde facto relationship with

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Note added at 2002-09-03 06:05:15 (GMT)
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We are not legally married.
we are having common-law marriage

など言い方もまた、主語が違ってもいろいろな言い方ができると思います。

Please refer to the Australian government's definition shown on the web page below.

just different wording.

or

living together in a de facto marriage.

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Note added at 2002-09-03 07:35:47 (GMT)
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or: in an unregistered marriage (I think this might suit if we¥'re talking about Japan)

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Note added at 2002-09-03 07:50:14 (GMT)
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If this is a 事実上の結婚 then I think de facto marriage is better than common-law marriage.

内縁 【ないえん】 (n) common-law marriage; ED
Full sentance translation:

"living in common-law marriage"

This is only known as a common-law marriage.

Common-law marriage has become further recognised in the UK, with people recognised as "living in a common-law marriage"

Note: Common-law marriages are not recognised by all US states:

http://www.unmarried.org/common-law-marriage.html

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