1.（2016·苏州）The earliest maps were probably drawn in the Middle East . Some of these maps have

   16    and they show us the people at that time thought the earth flat (平的) . As tim e went by , the pictures became more detailed and maps were more     17    made . Later on , ancient Greeks(希腊人) used their      18    of math and science to make maps . Greek maps tell us the Greeks knew the world was      19    .

From simple pictures , mapmaking has turned into a science . Maps are made      20    surveying(勘测) land . In the 1900s , people around the world started to share information to make