Theirs had been a happy and satisfactory marriage.
他们的'婚姻曾经一直幸福美满。
Our children go to the same school as theirs.
我们的孩子和他们的孩子上同一所学校。
It's a favourite game of theirs.
这是他们最喜爱的游戏。
It was a neighbourly gesture of theirs.
这是他们友好的表示。
There was a big group of a dozen people at the table next to theirs
他们旁边的桌上坐了一大群人，有十几个。