Part I

NB: This activity comes from Joanna Wolfe of Carnegie Mellon University. The CMU communication center developed this for use in faculty workshops “to explain our philosophy on grammar”; tutors in the center wrote both passages. (Click here for Wolfe’s discussion of this activity.)

Instructions: Here are two versions of an introduction to a research project written for a general audience. Which do you prefer: 1 or 2? (And see if you can explain why.)

  1. Polylactic acid (PLA) is a thermoplastic aliphatic polyester typically derived from corn starch, tapioca, or sugarcane. Current uses for PLA include biodegradable medical implants, packing materials, diapers and 3D printers. We propose a device that composts PLA and other bioplastics within a home composting environment [1]. PLA and other bioplastics may provide a sustainable alternative to petroleum plastics, which have staggering environmental impacts. PLA resembles traditional plastic and can be processed on equipment already used for petroleum plastics. PLA biodegrades under carefully controlled conditions, but it is only compostable in industrial facilities and cannot be mixed with other recyclable materials [2, 3]. This makes the commercial viability of PLA limited. We argue that our device would encourage the production of more sustainable and economic bioplastics.
  2. Although plastic has revolutionized modern life, the environmental impacts of traditional petroleum plastics is staggering. Bioplastics may provide sustainable alternative to petroleum plastics because it use fewer fossil fuels in production and reduce greenhouse gas emissions as they biodegrade. One particularly promising bioplastic are polylactic acids (PLA), a thermoplastic aliphatic polyester typically derived from corn starch, tapioca or sugarcane. PLA resembles traditional plastic and can be processed on equipment already used for petroleum plastics. However, the commercial viability for PLA is currently limited because is only compostable in industrial facilities and cannot be mixed with other recyclable materials [1, 2]. To make PLA more commercially viable, we propose a device that composts PLA and other bioplastics with home composting environment [3]. Such a device, we argue, would encourage production of more sustainable and economic bioplastics.

Part II

NB: Parts II and III are adapted from T. R. Johnson’s A Rhetoric of Pleasure (Heinemann, 2003), who in turn adapted from Joseph Williams’ Style: Lessons in Clarity and Grace (available in multiple editions).

Compare the following pairs of sentences, the original in column A, the revision in column B. What makes the revisions easier to read and process? What might writers want to do with the ordering of their information, based on what you see here? (And how might your observations here relate to what we discovered in part I, above?)

I suppose the evidence that UFOs have actually visited our planet is not very convincing to me for the most partI’m not much convinced by the evidence that our planet has been visited by UFOs.
Some astonishing questions about the nature of the universe have been raised by scientists exploring black holes in space. The collapse of a dead star into a point perhaps no larger than a marble creates a black hole. So much matter pressed into so little volume changes the fabric of space around it in puzzling ways. My favorite movie of all time actually deals with the issues surrounding black holes.Some astonishing questions about the nature of the universe have been raised by scientists exploring black holes in space. A black hole is created when a dead star collapses into a point perhaps no larger than a marble. Because black holes compress so much matter such small volume, the fabric of space around them changes in puzzling ways. The issues surrounding black holes are actually dealt with in one of my all-time favorite movies.

Part III

Now you try: Rewrite this paragraph based on the stylistic principle(s) we’ve identified.

Two aims—the recovery of the American economy and the modernization of America into a military power—were in the president’s mind when she assumed her office. The drop in unemployment figures and inflation, and the increase in the GNP testifies to her success in the first. But our increased involvement in international conflict without any clear set of political goals indicates less success with the second. Nevertheless, increases in the military budget and a good deal of saber rattling pleased the American voter.

Additional exercises: Revising for Cohesion