The only thing harder to write than introductions and conclusions are transitions between paragraphs and sentences. But they’re essential to good writing because they help guide your readers smoothly through the logical development of your ideas.
In the past I’ve tried to get students to understand the function of transitions by using different metaphors. I’ve talked about them as being like little conceptual “bridges,” or like links in a chain. But the problem with such metaphors is that they’re too static. They give the impression that transitions just act as passive and interchangeable “connectors” of sentences and paragraphs.
But a good transition—a thoughtful transition—is doing much more than merely connecting sentences and paragraphs. It’s dynamically moving your idea forward in the paper, to a nice, satisfactory, well-wrought conclusion. In this a good transition is much more like what’s going on in a relay race—the baton (the idea) is being smoothly passed on to the next runner, who sprints forward to smoothly pass it to the next, and so on.
Sometimes a single word can function as a perfectly fine transition, but these single “transition words” (the ones typically generated by Google searches) are certainly not interchangeable. Pick the wrong word and it’s like a dropped baton—the runner stumbles, and so does the progress of your idea.
So the general idea in a thoughtful transition is to facilitate the smooth forward movement of your thinking. Take up a bit of your thinking from what you’ve just written, and use it to fashion a transition that leads the reader smoothly into the next sentence or paragraph.
Bad transitions are also the result of poorly organized thoughts. Logic dictates that thoughts flow in a certain order, and this order should dictate the order of your sentences, and by extension, your paragraphs. Get your ideas in the right order. Think of each paragraph as a little story. Each story has a natural beginning, middle, and an ending, either chronologically- or logically-speaking. Getting your sentences in the right order will greatly aid you in writing transitions, both within and between your paragraphs.