posted by Cynthia .
What is subject-verb or pronoun-antecedent for this sentence:
Not one of our tomato plants are producing any fruit, but the greenbeans are thriving.
There is a grammatical error here. Not ONE is singular so the verb should be "Not one of our tomato plants IS producing any fruit, but the greenbeans are thriving.
The subject is One the verb is.
P.S. In the second clause "greenbeans" is the subject and the verb is "are."