Final answer:
The three sentences with correct subject-verb agreements are: Neither Sam nor Tom calls me by my nickname, Each of the trails ends at the bank of the Red River, and Much of the work is finished.
Step-by-step explanation:
In the given sentences, the three that have correct subject-verb agreements according to their pronoun subjects are:
- Neither Sam nor Tom calls me by my nickname. (singular subject)
- Each of the trails ends at the bank of the Red River. (singular subject)
- Much of the work is finished. (singular subject)