REVISING TO IMPROVE COHERENCE
Coherence describes the way that the elements in our sentences and paragraphs hang together to produce meaning. Usually when we write rough drafts, we are concerned mainly with getting our thoughts on paper, not with making sure that they interconnect well so that a reader can process our reasoning easily. We may even leave logical steps out.
Revising for coherence means going back to the draft with the reader's needs in mind. It may mean inserting transitional words and phrases, or creating parallelism so that the reader can see at a glance that a pair of elements carry the same weight, or rearranging material within a sentence so that the reader gets an accurate sense of what’s important and what’s not. Generally, it means instructing the reader on how to read our discourse.
The goal? Sharp focus.
It may be profitable to think of focus in terms of its original meaning. Borrowed without change from Latin, this word surprisingly first meant "hearth" or "fireplace" (compare fellow derivatives FOYER and FUEL)—in other words, that central point from which heat and light radiate throughout a structure. Focus entered the language of optical science with the sense of a place where things converge, and it is this sense of convergence and centrality and the sharp image that a correctly focused lens produces that we intend when we speak of FOCUS in writing.
Vegetation covers the earth, except for those areas continuously covered with ice or utterly scorched by continual heat. Richly fertilized plains and river valleys are places where plants grow, as well as at the edge of perpetual snow in high mountains. There is plant growth not only in and around lakes and swamps but under the ocean and next to it. The cracks of busy city sidewalks have plants in them as well as in barren rocks. Before man existed the earth was covered with vegetation, and the earth will have vegetation long after evolutionary history swallows us up.
(from Joseph Williams, Style)
The sentences contain sufficient information, but when read together they seem hazy, disconnected. It's not clear‑‑really‑‑what the main point is, even though one can sense the underlying logic. Note how the revising choices in the following version alleviate the problem. Then we'll look at the specific changes that were made.
Except in those areas continually covered with ice or scorched by continual heat, the earth is covered with vegetation. Plants grow not only in richly fertilized plains and river valleys but at the edge of perpetual snow in high mountains, not only in and around lakes and swamps but under the ocean and next to it. They survive in the cracks of busy city sidewalks as well as in barren rocks. Vegetation covered the earth before we existed and will cover the earth after evolution swallows us up.
This version is much more reader‑friendly because the writer has made the following changes:
(1) Shifted the material in the first sentence so that the main point comes at the end of the sentence. Readers expect the most important information to come at the end. By putting it there, the writer has insured that the reader will not interpret the exception ("except for . . .") to be what this paragraph is about. Instead, the reader can confidently go to the next sentence looking for examples of "the earth is covered with vegetation."
(2) Taken the six examples which make up the meat of the paragraph and put them in grammatically parallel constructions so the reader can see at a glance that they are all being used in the same way‑‑as examples. Note how in the revision, the grammatical subject is "plants" throughout the middle sentences, whereas in the previous version the subjects are "plains and river valleys," "plants," "plant growth," "the cracks of busy city sidewalks." The subject‑shifts in the original are abrupt and confusing.
(3) Strengthened the continuity from second last sentence to final sentence by beginning with "vegetation." "Vegetation" connects immediately with the previous sentences, whereas in the original version, the opening clause suddenly shifts us into a historical perspective in which the first grammatical subject is "man." Note also how the writer has sharpened the paragraph's focus‑-and hence the coherence‑‑by eliminating wordiness and strengthening the verbs.
Another sure‑fire way of improving coherence is to use transitional words and phrases. Such devices function like road signs. They signal immediately the logical relationship between parts of a sentence, or, if positioned near the beginning of a sentence, the relationship between that sentence and the sentence that preceded it. Any two consecutive sentences have an implicit logical relationship; often it helps the reader if you make the relationship explicit. In looking at the following list of transitions drawn from the Harbrace College Handbook, note the logical relationships indicated by the category headings:
1. Alternative and addition: or, nor, and, and then, moreover, further, furthermore, besides, likewise, also, too, again, in addition, even more important, next, first, second, third, in the first place, in the second place, finally, last.
2. Comparison: similarly, likewise, in like manner.
3. Contrast: but, yet, or, and yet, however, still, nevertheless, on the other hand, on the contrary, conversely, even so, notwithstanding, for all that, in contrast, at the same time, although this may be true, otherwise, nonetheless.
4. Place: here, beyond, nearby, opposite to, adjacent to, on the opposite side.
5. Purpose: to this end, for this purpose, with this object.
6. Cause, result: so, for, hence, therefore, accordingly, consequently, thus, thereupon, as a result, then, because.
7. Summary, repetition, exemplification, intensification: to sum up, in brief, on the whole, in sum, in short, as I have said, in other words, that is, to be sure, as has been noted, for example, for instance, in fact, indeed, to tell the truth, in any event.
8. Time: meanwhile, at length, soon, after a few days, in the meantime, afterward, later, now, then, in the past, while.
See the improvement in coherence that results when transitions are added to the following paragraph:
Cable television sounds like a good deal at first. All available local channels can be piped into a television set for a relatively low cost per month. The reception is clear‑‑a real bonus in fringe and rural areas. Several channels for news and local access are in the basic monthly fee. A cable connection to a second or third TV set costs extra. In most places subscribers have to pay as much as thirty dollars a month extra to get the channels like Home Box Office and The Disney Channel. The movies change each month. The pay‑TV movie channels run the same films over and over during a month's time. Many of the films offered each month are box office flops or reruns of old movies that can be viewed on regular channels. Cable television isn't really a bargain.
from Harbrace College Handbook
Cable television sounds like a good deal at first. All available local channels can be piped into a television set for a relatively low cost per month. And the reception is clear‑‑a real bonus in fringe and rural areas. Moreover, several channels for news and local access are in the basic monthly fee. On the other hand, a cable connection to a second or third TV set costs extra. And in most places subscribers have to pay as much as thirty dollars a month extra to get the channels like Home Box Office and The Disney Channel. While it is true that the movies change each month, the pay‑TV channels run the same films over and over during a month's time, and many of the films offered each month are box office flops or reruns of old movies that can be viewed on regular channels. In sum, cable television isn't really a bargain.
A final comment about transitional words and phrases: don’t overuse them. As historian Richard Marius observes, “when we use them too frequently to hold an essay together, they leave the rivets in our writing showing."