to arrive somewhere in order to join a group of people, especially late or unexpectedly

I invited him for eight o'clock, but he didn't show up until 9.30. 我请他8点钟来，可他直到9点半才露面。

We were expecting 30 people to come, but half of them never showed up. 我们以为会来30人，但有一半人根本没露面。

to behave in a way that makes someone you are with feel ashamed or embarrassed

I wish you wouldn't show me up in front of my parents by getting so drunk. 我希望你不要醉成这样，让我在我父母面前难堪。