To show someone up means to do something better than someone else, it usually means to make the other person look bad by doing something better than them.

to show someone means to do something better than someone, it usually means to show someone up means to do better something than someone, it usually means to make other person look bad by doing something better than them. 这通常意味着通过做一些比他们更好的事情来让对方看起来很糟糕。