a. 按重要性顺序排列（arrangement in order of importance） if you work as a soda jerker, you will, of course, not need much skill in expressing yourself to be effective. if you work on a machine, your ability to express yourself will be of little importance. but as soon as you move one step up from the bottom, your effectiveness depends on your ability to reach others through the spoken or the written word. and the further away your job is from manual work, the larger the organization of which you are an employee, the more important it will be that you know how to convey your thoughts in writing or speaking. in the very large business organization, whether it is the government, the large corporation, or the army, this ability to express oneself is perhaps the most important of all the skills a man can possess. 这一段谈的是表达能力，它的重要性与职业，身份有关，从“not need much skill”或“of little importance”到“more important”，最后是“most important”。 b.由一般到特殊排列（general-to-specific arrangement） if a reader is lost, it is generally because the writer has not been careful enough to keep him on the path. this carelessness can take any number of forms. perhaps a sentence is so excessively cluttered that the reader, hacking his way through the verbiage, simply doesn't know what it means. perhaps a sentence has been so shoddily constructed that the reader could read it in any of several ways. perhaps the writer has switched tenses, or has switched pronouns in mid-sentence, so the reader loses track of when the action took place or who is talking. perhaps sentence b is not logical sequel to sentence a —— the writer, in whose head the connection is clear, has not bothered to provide the missing link. perhaps the writer has used an important word