Several people have influenced my writing over the years. The first would be my grade school teachers as a whole and Mrs. Ellington, my 8th grade English teacher in particular. Back in the dark ages we were taught sentence construction by diagramming the sentence. At the time, this was torture, but later on a saw the value when I realized how many people have no idea how to write a sentence.
Later when I was working at General Foods, I was sent to various classes on writing. Most of these were a total waste of time, but one class emphasized that business writing should be clear, economical and always in active voice. It takes more words to say things in passive voice and you can't convince people you really mean it when you're talking from behind the issue rather than in front.