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が三人いる

has three (people)

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phrase Rare #34,222
has three (people) Used to say that someone has three people in their family, such as three siblings or children.
JA: 私には姉が三人いる。
EN: I have three older sisters.

彼女には兄弟が三人いる。

She has three siblings.

妹が三人いる。

I have three younger sisters.

トムには成人した子供が三人いる。

Tom has three grown children.

私の叔父には子供が三人いる。

My uncle has three children.