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Most people don't think pigs are smart, but sometimes they are really smart. Frank and his wife（妻子）Laura live in Canada. Laura is fifty-eight years old and she is not very healthy. They like going for trips when they are free.
One day, after Frank finds a new job, they go to a village to see their old friend Alan. After lunch, they go outside. Frank is good at swimming, so he asks Alan to go swimming in the river. Laura goes boating first and then she takes a walk with their pets Bill and Lulu near the river. After half an hour, she doesn't feel well. Then she falls down（跌倒）. At this time, her dog Bill and pig Lulu are with her. Bill just keeps quiet there, but Lulu, the fat pig, runs to the river and takes Frank back to Laura. Seeing Laura, Frank knows she is in great danger and he takes her to hospital. Thanks to Lulu, Laura feel well at last. She tells Alan that Lulu saves her life. What a smart pig!