情态动词 can 的基本用法 — 英语阅读题

阅读短文，回答问题。 My name is Ben. I am nine years old. I can swim very fast, but I can't skate. My sister Alice can skate, but she can't swim. My friend Joe can play football, but he can't swim either. On Sunday, we go to the park together. Alice says to me, "Can you skate?" I say, "No, I can't, but I can teach you to swim!" Question: Who can skate but can't swim? (用简短英语回答)