填空题 A．frequently B．adolescence C．separate D．complexion
E．unformed F．set G．genealogy H．appearance
I．commonly J．single K．alike L．populated
M．produced N．startling O．genetics
Perhaps the most 31 theory to come out of kinetics, the study of body movement, was suggested by Professor Ray Birdwhistell. He believes that physical 32 is often culturally programmed. In other words, we learn our looks—we are not born with them. A baby has generally 33 facial features. A baby, according to Birdwhistell, learns where to set the eyebrows by looking at those around—family and friends. This helps explain why the people of some regions of the United States look so much 34 . New Englanders or Southerners have certain similar facial characteristics that cannot be explained by 35 . The exact shape of the mouth is not 36 at birth, it is learned after. In fact, the final mouth shape is not formed until well after permanent teeth are set. For many, this can be well into 37 . A husband and wife together for a long time often come to look somewhat alike. We learn our looks from those around us. This is perhaps why in a(an) 38 country there are areas where people smile more than those in other areas. In the United States, for example, the South is the part of the country where people smile most 39 . In New England they smile less, and in the western part of New York state still less. Many southerners find cities such as New York cold and unfriendly, partly because people on Madison Avenue smile less than people on Peachtree Street in Atlanta, Georgia. People in densely 40 urban areas also tend to smile and greet each other in public less than people in rural areas and small towns do.