Similarity predicts the success of a marriage and through a phenomena people aren't exactly sure about, couples become more and more similar over the course of a relationship.

相似性能预测到一段婚姻是否会成功,人们也解释不清这个现象，相处久了，夫妻之间就有了夫妻相。

耶鲁公开课 - 心理学导论课程节选