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  A 1987 survey was given to 5,000 high school seniors. It showed that they did not know geography. Students in Boston were questioned. One-third of them could not (1) six New England states. Students in Baltimore were questioned. Half could not shade in the United States on a map. Here is what another survey showed. Students did not know (2) . Most did not know the dates of the American Civil War. Many did not know World War Ⅱ leaders.
  Someone else asked this question. What did students (3) of social studies Their answer: social studies were not important. They said it was the (4) important of their studies.
  What are social studies It is the study of (5) . It is the study of groups. It is the study of societies. Social
  

Dear Philip,
Your birthday is coming some days later. Your parents must get ready for a big birthday cake for you. Although we are far apart on both sides of the ocean, we are together for ever, "Friendship brings beauty to our days, joy to our world".
Somehow it just comes naturally to wish nice things for you, because you are so nice in everything you say and do and all life’s best things always for the nicest kind of friend! Happy Birthday!
Yours Cordially
Mary
Dear Mary,
I am very glad to have received your letter. Thank you very much for your warm wishes for my birthday. I can’t help thinking of the very pleasant occasion that I enjoyed at the nice dinner you gave me at your home in Wuhan on my birthday last year. Today I am celebrating it with my family and have told them about my birthday in Wuhan. I hope for an opportunity to meet you and reciprocate you here in Canada.
With the best wis