to go back on one's word
01
to fail to keep a promise or commitment that was previously made
![to [go] back on {one's} word definition and meaning](https://cdn.langeek.co/photo/70259/original/?type=jpeg "to [go] back on {one's} word definition and meaning")
搭配
例子
He had promised to help me with the project, but he ended up going back on his word.
to fail to keep a promise or commitment that was previously made
