There are a few ways you can examine prior paraphrase inputs:
1. Use the prior paraphrased sentence option.
When you're paraphrasing individual sentences in the right side of the paraphraser, there is a rephrase and an undo option when you select a sentence, as shown below:
If you use the Undo button, this will revert the paraphrased sentence to the prior paraphrase.
2. Use the "History" button.
This is a Premium-only feature that allows you to see the original and paraphrased version of each of your inputs. You can access it by clicking on the clock-like icon on the right side of the paraphraser interface.