“that cat won't jump”别理解成“那只猫不会跳”，其正确的含义是那个想法行不通，那个建议不现实。

【例句】
I hear many saying that we ought to do away with taxes altogether, but I'm afraid that cat won't jump.
我听到很多人说，我们应该完全取消税收，但我觉得那个想法行不通。

He suggested the boss cancel the paid vacation. But we believe that can won't jump.
他建议老板取消带薪休假，但是我们觉得那个想法行不通。