[originaltext] (16)There is probably no area of human activity in which our

(16)There is probably no area of human activity in which our values and lifestyles are reflected more vividly than they are in the clothes that we choose to wear. The dress of an individual is a kind of " sign language" that communicates a complex set of information and is usually the basis on which immediate impressions are formed.(17)Traditionally, a concern for clothes was considered to be a feminine preoccupation, while men took pride in the fact that they were completely lacking in clothes consciousness. Times have changed as masculine dress takes on greater variety and color. As early as 1955, research revealed that men attached high importance to the value of clothing in daily life. White-collar workers in particular viewed dress as a symbol capable of manipulation(控制), which could be used to impress or influence others, especially in work situations.(18)Although blue-collar workers were less aware that they might be judged on the basis of their clothing, they recognized that any difference from the accepted pattern of dress would draw scoff from fellow workers. Since that time, the pattern has changed: the typical office workers may now be wearing the blue shirt, and the laborers the white shirt: but the importance of dress has not diminished.
Questions 16 to 19 are based on the passage you have just heard.
16. What can our clothes do according to the passage?
17. What can we know about men in the past?
18. What can we learn about blue-collar workers according to the research of 1955?
19. What is this passage mainly about?