their

their
possessive determiner
  1. belonging to or associated with the people or things previously mentioned or easily identified
    他们的;她们的;它们的
    parents keen to help their children.
    热衷于帮助孩子们的父母。
    ■belonging to or associated with a person of unspecified sex
    (指性别不确定的人)他的;她的
    she heard someone blow their nose loudly.
    她听到有人大声地擤鼻涕。
  2. (Their)used in titles
    (用于头衔)陛下;殿下;阁下;大人
    a double portrait of Their Majesties.
    国王和皇后陛下的双人肖像。
语源
  1. Middle English: from Old Norse their(r)a 'of them', genitive plural of the demonstrative ; related to them and they
用法
  1. 2 On the use of their in the singular to mean ‘his or her’, see usage at they
英语宝典
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