Passage 3

Questions 11 to 15 are based on the following passage．

     Postage stamps are labels affixed to letters or parcels to indicate that a specified amount of postage has been prepaid for delivery．Stamps are usually issued by a government or an agency representing a government，such as a national post office．The collecting and study of postage stamps and related items such as postcards is known as philately, a word derived from Greek meaning，literally, “love of what is free of further tax．’’Stamp collecting is one of the most popular hobbies in the world．

     From the earliest years of the hobby，most philatelists have preferred to collect stamps by country，specializing in the issues of one or more nations．Since about the mid-1950s，however, many philatelists have become interested in topical collecting，acquiring stamps illustrating certain themes or subjects．Among the wide range of pictorials are stamps devoted to sports，art and music，aviation，birds and flowers，and telecommunications．

     One of the attractions of stamp collecting is the ease of starting a collection．With access to enough incoming mail，especially from abroad，a person call build a collection without any expense．Literally tens of thousands of stamps，however, including many of the older issues，are priced very cheaply．

    Little special equipment is required．A collector needs only an album to house the collection and a pair of stamp tongs with which to handle them．Stamps and accessories can be purchased easily．Nearly every city has one or more professional stamp dealers．Thousands of other dealers operate exclusively by mail or on the Internet．

     When collectors have accumulated a number of valuable stamps，they must take precautions for safe storage，preferably in a bank safety deposit box．If the stamps are in mint(崭新的)condition，they should not be overlapped；through changes in humidity, overlapping stamps may stick together and become seriously damaged．Collectors also should keep accurate written inventories of all their philatelic material．

In the 1st paragraph，“philately” is a term dealing with ______．