If you say that someone is in a rut, you disapprove of the fact that they have become fixed in their way of thinking and doing things, and find it difficult to change. You can also say that someone's life or career is in a rut.
双语例句
例： I don't like being in a rut – I like to keep moving on.
我不喜欢一成不变–我喜欢不断前进。