36. A post office is open in America. A. on Saturday mornings B. from Monday till Friday C. every day from 8: 30 to 4: 30 D. from Monday to Friday and Saturday mornings
At a post office you can also buy postcards. A postcard is cheaper than a letter. Usually the price of postage for a postcard is about half that of a letter. The postcards you buy at a post office do not have pictures. They are also not to be sent outside the country.
Letters are an easy and cheap way to communicate(交流)with people in many different countries.