Here are the correct answers for each sentence:
That's a good book. It a. was written by George Orwell.
The meeting c. will be held in Room 20 soon.
She c. hasn't bought a new dress for three years.
She b. doesn't understand how to do Sudoku.
I b. was offered an interesting job yesterday.
Smoking a. is not allowed here.
A school c. will be built in this area next year.
The kids b. swam in the sea yesterday.
Jane a. is my best friend for many years.
The doctor b. was ... sent immediately for last night.
The parcels b. are often received by soldiers in the army.
If you have any further questions or need more practice, feel free to ask!