—고
Use —고 to link two actions or events in one sentence. It often means "and" or "and then." In the story, "깜짝 놀랐고 모두가 웃었어요" links two events. You can reuse it like this: "친구를 만나고 같이 케이크를 먹었어요."
친구를 만나고 같이 케이크를 먹었어요.
I met my friend and ate cake together.
