Re. Karen's sentence structure query

[Geoff Hart <geoff-h -at- MTL -dot- FERIC -dot- CA>]

     Karen Mayer asked whether to place the context up front in an
     instructional sentence, or at the end, after the action. As always,
     Karen, it depends:

     1. Since context should always precede elaboration, the context should
     generally come at the beginning of the sentence. Thus, "to perform A,
     do B". Note that this greatly facilitates skimming too: readers need
     only read the first three words (in this example) to determine whether
     they should continue reading or skip to the next line. Think of this
     as the sentence equivalent of a heading; indeed, for some processes,
     you can use the context as the heading for a series of short steps,
     none of which need include the context since it's right there at the
     beginning in the heading.

     2. However, advocates of metadiscourse would immediately point out
     that sometimes context must come at the end of the sentence to build a
     bridge with the following sentence and to alert readers to the
     consequences of their actions. Thus, "To perform A, do B; this will
     take you to the C screen. To do D (in the C screen), ...."  Note that
     this serves another important function: if readers don't hit the C
     screen after this step, they know something's wrong; if they do reach
     the screen, they know they've succeeded at this step.

     3. If the context is a warning that will prevent injury or data loss,
     then the context _must_ come first, since some people (myself being
     one all too often) immediately perform the instruction without reading
     the context at the end of the sentence. Thus: "To avoid electrocution
     while attaching the component, make sure the power is off." The "e"
     word will certainly focus attention on the hazard, then introducing
     the context (attaching) provides additional context. You could argue
     that "make sure that the power is off" could come first, but some
     readers will ignore this command, rationalising that they can probably
     skip this step (particularly if the step is more complicated or
     inconvenient than simply switching off the power). Thus, put the
     warning first.

     So the short answer becomes: "you'll have to examine an instruction to
     see which of these three cases applies". There aren't any absolute
     rules in writing, only really good guidelines based on how people
     read. In general, the context should come first, but there will be
     exceptions.

     --Geoff Hart    #8^{)}
     geoff-h -at- mtl -dot- feric -dot- ca

     Disclaimer: If I didn't commit it in print in one of
     our reports, it don't represent FERIC's opinion.