be joined at the hip
彼此紧密地联系在一起，无法分开
口语·形容关系极其亲密
英文释义
to be extremely close or inseparable, often referring to two people who spend a lot of time together and do everything together
例句
Those two friends are joined at the hip; you never see one without the other.
典故来源
源自连体双胞胎的医学现象，比喻两人形影不离。