pron.他(她,它)们的,在提及性别不详的人时,用以代替 him 或 her
Theirs had been a happy and satisfactory marriage.
他们的婚姻曾经一直幸福美满。
This child is nobody's child until someone makes her theirs officially.
在有人办理正式手续认领以前,这个孩子不属于任何人。
Theirs had been an increasingly attenuated relationship.
他们的关系日益冷淡。