A.
DENIS: Vote - They did not vote.

CORRECT!

B.
DENIS: Governor - Run in the governor election.

CORRECT: Run for the governor election.

EXPLANATION: The preposition 'in' and 'for' has different usage. We usually use 'in' for MONTHS,YEARS, CENTURIES and LONG PERIODS.
Examples :
- In May I will start studying English.
- In Summer I will go to Canada.
- In 1990 the biggest bird was born.
On the other hand we use 'for' to indicate the use of something, time, the cause of the reason and duration.
Examples:
- I baked a cake for your birthday.
- For this reason, I've decided to quit this job.
- I attended the university for one year only.

C.
DENIS: President - The president elect.

CORRECT: The president has been elected.

EXPLANATION:
- We need the verb to be on it's present perfect continuous tense. We often use the present perfect tense to talk about a continuing situation. This is a state that started in the past and continues in the present (and will probably continue into the future). This is a state (not an action). We usually use for or since with this structure.

COMMENT:
Hello Denis!
Thank you very much for sending me your homework. I'm glad to know that you are trying your best on making your own sentences. I know you are a very smart kid and I know that you can make better sentences than this next time. We just need to have continuous practice. Keep it up and see you again later. Good job for this homework!
-Teacher Joanna