👉 A nonsubordinating clause is a clause that does not refer to something that is already subordinate. It refers to a clause that acts as an alternative to another clause, rather than being subordinate to it in some way.
For example:
"I would like to buy this book."
"This book is my favorite."
In this case, the nonsubordinating clause "this book" does not refer to something else and is considered a synonym for the other clause.