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如图,是某同学在上学路上的情景,由于风大伞被吹得向上翻起,伞向上翻是由于伞的下表面风速比上表面的风速____,从而使伞的下表面受到空气压强比上表面大所致.学生背的书包,书包带通常都比较宽大,这有助于减小书包对肩膀的____

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    Mother's Day is a time of commemoration (纪念) and celebration for Mom. It is a time of breakfast in bed, family gatherings, and crayons scribbling "I Love You".

The earliest Mother's Day celebrations can be dated  (1)   to the spring celebrations of ancient Greece in honor of Rhea, the Mother of the Gods. During   (2)   , England celebrated a day called "Mothering Sunday". "Mothering Sunday" honored the mothers of    (3)  . In the United States Mother's Day was first suggested in 1872by Julia Ward Howe. In 1907, Anna Jarvis, from Philadelphia, began a campaign (运动) to establish (建立) a    (4)   Mother's Day. Ms Jarvis persuaded (说服) her mother's church in Grafton. West Virginia to celebrate Mother's Day on the second anniversary (周年纪念日) of her mother's   55  , the 2nd Sunday of May. And the next year Mother’s Day   56   in Philadelphia. Ms Jarvis and her supporters began to    57   officials, businessmen, and politicians in their quest to establish a national Mother’s Day. It was successful.   58    1911 Mother's Day was celebrated in almost every   59   . President Woodrow Wilson, in 1914, announced Mother's Day as a national holiday that was to be held on the 2nd Sunday of May each year.

While many countries of the world celebrate their own Mother's Day at   60   throughout the year, there are some countries such as Denmark. Finland, Italy, Turkey, Australia, and Belgium which also celebrate Mother's Day on the second Sunday of May.