Although the causes of cancer _____, we do not yet have any practical way to prevent it.
We should realize the fact that when you graduate from university, you are still not prepared for the possible situations ________ we may face in the working world.
—How are things going, Janet?—They have set out to deal with the present situation ________ they think deserves their immediate attention.
Have you ever dreamed of staging a concert, ________ thousands of people are applauding and appreciating your music?
—How do you like the book?—It's quite different from ________ I read last month.
Suddenly I heard a man shouting at a driver, ________ car was blocking the street.