B6: Subject-Verb Agreement, Subject Follows the Verb: In some cases, the subject of the sentence comes after the verb, but the subject and verb still need to agree. See Writing for Success Section 2.2 p. 61 or RULE 9 at the following:https://writing.wisc.edu/handbook/grammarpunct/subjectverb/
Are birds really the descendants of dinosaurs?
(Birds are really the descendants of dinosaurs.)
“There is/There are” sentences:
There is an awful smell in this basement.
(An awful smell is in this basement.)
There are fifteen old cannonballs in the courtyard.
(Fifteen cannonballs are in the courtyard)