a stiff brush的用法和样例：
- She cleaned the sink with a stiff brush.
- First try brushing the floor thoroughly with a stiff brush.
- These, in addition to the power drill and handgun, included the use of a stiff brush on a detainee and stepping on a detainee's ankle shackles.
- scrape the floor with a stiff brush
- Stir the flour and milk to a stiff paste.
- That was a shock I need a stiff drink!