have a hard mouth

• 不听使唤；不好驾驭

have a hard mouth的用法和样例：

例句

1. I have steered my course by our enduring valuess.
   借助我们永恒的价值，我驾驭了我的航程。
2. It is difficult to rein a fiery horse.
   脾气暴躁的烈马是难于驾驭的。