Fourth, as you enter in front of the door, knock at the door first , receiving the teacher and getting back to the seat after allowing, you will be very happy, because you are a courteous child;

第四，当你进门前，先敲一下门，得到老师允许后回到座位，你会很快乐，因为你是一个有礼貌的孩子；

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Decades later, segregation still ruled America, and when Sports Illustrated invited Winkfield to a reception at the Brown Hotel in Louisville in 1961, he was told he couldn't enter by the front door.

CNN: The forgotten godfathers of black American sport