you cannot make a crab walk straight直译你无法让螃蟹走直线，引申为江山易改本性难移，不要试图去做不可能的事。

【例句】
There is a saying that goes，you cannot make a crab walk straight!
有句话说的好，江山易改本性难移。

Why are you try to teach her this game when she clearly isn't interested? You cannot make a crab walk straight, you know.
为什么你要带他玩这个他不感兴趣的游戏？江山易改本性难移，你懂的。