服装类词汇（shirt, dress等） — 英语阅读题

阅读短文，回答问题。 Today is Monday. In the morning, Amy gets dressed for school. It is cold outside. She puts on a white shirt first. Then she puts on a blue coat over the shirt. She also wears black trousers. At school, her friend Peter wears a green sweater. Peter is not wearing a coat today, because it is warm in the classroom. Their teacher Miss Li wears a red dress. In the afternoon, Amy takes off her coat and hangs it on the chair. Now we can see her white shirt again. Question: Who is wearing a dress today? What colour is it?