Stay on one topic
In 90 percent of situations, it’s best to keep a paragraph focused on one topic. Yes. ONE topic. There is nothing worse than a paragraph that starts discussing one topic and then, mid-paragraph, switches to another topic. It can be very confusing, not to mention frustrating, for a reader when their thoughts are suddenly directed from one area of thought to another in the middle of a paragraph. If you’re in the middle of a paragraph and something suddenly comes to mind that you think you should discuss, do not tack it onto the current paragraph - start a new one.
In this example paragraph, we read the first sentence and work out that the paragraph is going to be about the dinosaur Tyrannosaurus Rex. The next two sentences go on to talk about its claim to being the largest carnivore ever to walk the earth. These sentences are sort of linked to what appears to be the topic of the paragraph, so they’re OK. However, the last sentence about Giganotosaurus is a little bit too off topic. We’d be much better off starting a new paragraph with Giganotosaurus as the new topic of discussion:
Click here to move on to the next topic: Parts of a paragraph