Question

I need help determining what the simple subject and the complete subject is in the following sentence.

There are no known allergies.

There is the simple subject?
I'm not sure what the complete subject is.
Thanks for your help.
Writeacher
No, sorry. This time the sentence is exhibiting reverse word order.

There = introductory word
are = main verb
allergies = main subject
no & known are adjectives modifying the subject