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Erna Hart is going to swim across the English Channel tomorrow. She is going to set out from the French coast at 5 o’clock in the morning. Erna is only 14 years old and she hopes to set up a world record. She is a strong swimmer and many people feel that she is sure to succeed. Erna’s father will set out with her in a small boat. Mr Hart has trained his daughter for years. Erna intends to take short rests every two hours. She will have something to drink but she won’t eat any solid food. Most of Erna’s schoolfriends will be waiting for her on the English coast. Among them will be Erna’s mother, who swam the Channel herself when she was a girl.
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How long has Mr Hart trained his daughter?