John is six years old. He can read and write well. But he can't tell the time. He says "breakfast time", "lunchtime", and "teatime" when it is eight o'clock, twelve o'clock and four o'clock in the afternoon. His mother doesn't know how to help him. One day John's aunt, Mary, comes to see his mother. His mother tells her about that. "Let me help you. I think I can help him." When John gets home after school, Mary starts to teach him. "Can you _ , John?" she asks him. "Yes. One, two, three, four..." John says. "That's great. Now I put the longhand on twelve and the shorthand on one - that is one o'clock. I put the short hand on two, what is the time?" "Two o'clock." "Good. And on three?" "Three o'clock." It is then four o'clock in the afternoon, and John's aunt asks him, "What time is it now, John?" "Teatime, Aunt." John looks at the clock and answers. Mary is John's   _  .
mother aunt teacher sister