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Mr. Black is a doctor. He works in a big hospital. It's far away from his home to the hospital. He often comes back home late and often forgets(忘记) his family's birthday. But last Saturday afternoon after doing his work, he suddenly remembered(记起) it was his wife's (妻子的) birthday. Soon on his way home, he went into a flower shop to buy some beautiful flowers. Mr. Black got home and gave his wife the flowers and said to her," Happy birthday to you!" Mrs. Black saw these beautiful flowers, laughing and saying. " My birthday is on the twentieth of May, not today, but thank you for giving my birthday present(礼物)."