PHRASE 介于两个状态之间的;将要进入特定状态的 If you say that someone or something is on the cusp, you mean they are between two states, or are about to be in a particular state. 介于两个状态之间的;将要进入特定状态的
I am sitting on the cusp of middle age. [+ of]
我将步入中年。
Mr Short's behaviour is only on the cusp of acceptability.