前/他的 + 妻
The noun 妻 (qī) means "wife" and is a classical or formal way to refer to a married woman in relation to her husband. In modern Chinese it most often appears in compound words like 妻子 (qīzi, wife) or 前妻 (qiánqī, ex-wife).
他和妻子结婚已经二十年了。
Tā hé qīzi jiéhūn yǐjīng èrshí nián le.
He and his wife have been married for twenty years.
他的前妻现在住在上海。
Tā de qián qī xiànzài zhù zài Shànghǎi.
His ex-wife now lives in Shanghai.
夫妻俩一起经营着一家小店。
Fūqī liǎ yīqǐ jīngyíng zhe yī jiā xiǎo diàn.
The couple runs a small shop together.