-----“Where did you find the professor who made the speech yesterday?”-----“It was in the hall ______ the students often have a meeting.”
--- Have you finished the book? --- No, I’ve read up to _______ the children discover the secret cave.
He was late for the meeting _________ the heavy snow.
They tried to convince her _______ his innocence.
We can never expect ______ bluer sky unless we create _______ less polluted world.
Was he sorry for what he’d done ?