Abstract
Many current technical writing handbooks still advise writers to avoid the passive voice except in certain limited situations, primarily when the agent is unknown, understood, unimportant, or better left unnamed. However, a growing body of research indicates that the passive voice has a broader array of rhetorical functions. To identify some of the functions of the passive, as well as the active, voice, the frequencies of active and passive verbs were determined in 185 documents written by twenty-eight civilian and military members of the U.S. Air Force. The frequencies were similar to those in similar types of documents written by nonacademic writers in previous studies. In addition, writers were queried about their reasons for choosing active or passive verbs. While the results of the study confirmed the importance of agency in the choice of active or passive, they also revealed numerous other factors that were significant in writers' choices. The most significant reasons for choosing one type of verb over another were the voice of the verb, organizational requirements, audience awareness, efficiency, genre, euphony, personal preference, agency, emphasis, and topic-comment flow. These results suggest that technical writing instruction and handbooks should promote general principles for the use of both active and passive verbs rather than advising against the use of passive verbs.