Hi Jon and Meg,
I was going to add that as well. Phrases that are behind or between commas like Meg shown can be easily interchanged. Other than that, other examples include:
Jim's dog is really cute.
The dog, which belongs to Jim, is really cute.
The doctor did his very best.
The man, being a doctor by trade, did his very best.
My apple is going to be eaten.
The apple, which belongs to me, is going to be eaten
In other words, phrases without commas can be restructured to have certain words in between commas.
Additionally, other sentence structures that can be changed are also changing the position of adjectives:
The fancy car is going to go out now.
The car that's fancy is going to go out now.
The big dog is eating the steak
The steak was eaten by the big dog
The steak was eaten by the dog that's big.