Paraphrasing is useful because it forces you to check the parts of the concept (elements and their relations) you are about to explain. While just giving something back word-by-word could hide the lack of understanding, if you understand the concept, you should be able to give back the details in a different order/point of view. If you understood the main parts, and how they are connected, you can give a different explanation (changing the order/showing different sides, replace parts etc), while also retaining the meaning of the content. While trying to do this, you have to make sure all details are connected properly (and are actually observed, as a lot of them may be be assumed to be known implicitly), otherwise you will not be able to follow through with the exercise.
A good analogy could be building a lego object: if I show you how to do it, and then you have to assemble it again from scratch, you should be able to succeed in this while starting at a different part and adding the blocks in a different order than I did. This requires a much better understanding than just copying the very moves I made in the same order.
Example: I explain to you, how to make an omelette (heat up pan, put on oil to avoid the eggs sticking to it, pour scrambled eggs into the pan, use the spatula to optimize form/density, add grated cheese then fold the sides on top). To paraphrase the process back to me, you should understand how the steps are connected, so even if your circumstances are different, you can replace/move around object to fulfill the meaning: the point is to scramble and fry eggs on an open surface without burning them.* If you do not have a pan, a pot may suffice, you can use butter instead of oil, and so on.
*a valid point could be made that omelette is more than that, please excuse the simplification I made for demonstration.
Exercise:
Paraphrasing is useful because it forces you to check the parts of the concept (elements and their relations) you are about to explain. While just giving something back word-by-word could hide the lack of understanding, if you understand the concept, you should be able to give back the details in a different order/point of view. If you understood the main parts, and how they are connected, you can give a different explanation (changing the order/showing different sides, replace parts etc), while also retaining the meaning of the content. While trying to do this, you have to make sure all details are connected properly (and are actually observed, as a lot of them may be be assumed to be known implicitly), otherwise you will not be able to follow through with the exercise.
A good analogy could be building a lego object: if I show you how to do it, and then you have to assemble it again from scratch, you should be able to succeed in this while starting at a different part and adding the blocks in a different order than I did. This requires a much better understanding than just copying the very moves I made in the same order.
Example: I explain to you, how to make an omelette (heat up pan, put on oil to avoid the eggs sticking to it, pour scrambled eggs into the pan, use the spatula to optimize form/density, add grated cheese then fold the sides on top). To paraphrase the process back to me, you should understand how the steps are connected, so even if your circumstances are different, you can replace/move around object to fulfill the meaning: the point is to scramble and fry eggs on an open surface without burning them.* If you do not have a pan, a pot may suffice, you can use butter instead of oil, and so on.
*a valid point could be made that omelette is more than that, please excuse the simplification I made for demonstration.