1. union of concubinage
夫妾关系

-- 来源 -- 英汉 - 翻译参考[网络]

2. This system of marriage and concubinage made women experience a disastrous decline in terms of their social position.
周代这种异姓嫡媵婚制,使周代女性地位一落千丈。

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3. child of a union of concubinage
夫妾关系中的子女

-- 来源 -- 英汉 - 翻译参考[网络]

4. True, they were not slaves, but neither were they free; they could not marry free persons, and their marriages with one another were not regarded as full marriages, but, like those of slaves, as mere concubinage (contubernium).
这种隶农虽不是奴隶,但也不被认为是自由人,他们不能和自由人通婚,他们相互间的婚姻也不被认为是合法的,而是像奴隶的婚姻一样,只被看作简单的同居(contubernium)。

-- 来源 -- 家庭、私有制和国家的起源 - jiatingsiyouzhi_10

5. consensual union; companionate marriage; concubinage
自愿的结合; 习俗婚姻; 同居; 习惯婚姻

-- 来源 -- 英汉 - 翻译参考[网络]

6. This phenomenon, the concubinage, appeared first in the Wei and Jin dynasties, became the rage in the Sui and Tang dynasties, and acquired legitimacy after the Song Dynasty.
这种现象产生于魏晋,盛行于隋唐,两宋以后变成公开合法。

-- 来源 -- 网友提供