他們的名詞性物主代詞用英語怎麼說

　　Theirs had been a happy and satisfactory marriage.

　　他們的'婚姻曾經一直幸福美滿。

　　Our children go to the same school as theirs.

　　我們的孩子和他們的孩子上同一所學校。

　　It's a favourite game of theirs.

　　這是他們最喜愛的遊戲。

　　It was a neighbourly gesture of theirs.

　　這是他們友好的表示。

　　There was a big group of a dozen people at the table next to theirs

　　他們旁邊的桌上坐了一大群人，有十幾個。