a three person family 或者 a three member family
补充一下:英语跟中文一样,同一种意思可以有许多种不同的表达方式,给你回复的人说的都对,除了a family which has three people,这句话语法有点问题,不是太恰当,person 是单数,people 是复数,三个人,每一个人都是不同而且单数的,应该说：a family which has three person.
如果想用复数 ,除非是三个人都一样,比如说,a family which has three girls.家里有三个女儿,三个女儿性别等等都是相同的,用复数.我想你指的一家三口肯定指的,你,你母亲,你父亲,三个不同的人.所以用单数较好.A family which has three person .
实际上 除此之外,一家三口有许多不同的表达方式,向；
A family with three person/member,a family having three person/ member ,a family consisting of three person …
等等,
我原来只给出a three person family 或者 a three member family,是因为觉得他们最好,国外跟中国一样,语言讲究简洁,句子越短越好,无论口语还是新闻,他们通常说a three person family 或者 a three member family,其中a three person family
说的更多一些,所以我把它摆在第一位.
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