The basic idea of when to begin a new paragraph is begin one when you are introducing a new thought. Maybe that’s not clear. We’re talking a major thought that needs a cluster of sentences or maybe just one or maybe just a sentence or two and some fragments.
Checking “Paradigm Online Writing Assistant,” I found, “A paragraph is a visual cue for readers. The indentation at the beginning, like the capital letter at the start of a sentence, signals your reader that a new thought unit is about to begin. Just as sentences gather words and phrases into units of meaning, these sentences are gathered into paragraphs. The paragraphs, in turn, may be gathered into major subdivisions…. Since paragraphs help readers see important thought units, a general guideline would be to start a new paragraph whenever you begin writing about a new organizational topic. But this won't always work. In practice, you may find that two or three minor points can be treated in a single paragraph, or you may discover that what at first looked like a single sub point is growing so big that it needs to be broken up [emphasis added]… remember that paragraphs cue your readers to important thought units below the level of your lowest subheading, yet above the level of the sentence…”
Remember you are using paragraphing to help your readers. Often, as in a letter, for example, writing begins with the vaguest of plans. But, you have a built-in guide here – your own “instinct” about when a paragraph needs to end, another to begin. Follow that “instinct.” It’s usually reliable and based on your lifetime subconscious observances about communication. OK, some people’s are stained purple and tattooed or something.
Too many short paragraphs make the piece very choppy. Too many long paragraphs produce somnolence in the reader. Or loss of reader.
In writing with direct quotations, always change paragraphs when speakers change. This is an enormous help.
OK, I know you miss the ONLINE DEPARTMENT, a source of joy and happy smiles in the midst of the chilly rain of Christmas shopping and remembering where you hid the decorations last January and then finding them all wadded up and moldy. ONLINE DEPARTMENT WILL RETURN.
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