I remember her face but I cannot _____ where I met her.
There is no doubt that by recycling textbooks, the cost of books will be __________ greatly.
I agree with most of what you said, but I don't agree with __________.
—Do you know the man __________ is talking with your father?—Yes, he's our headmaster.
__________ David says sounds right to Helen. That's why she has made up her mind to leave with him __________ happens.
I hadn't seen my old friend for many years, so I didn't __________ his voice on the phone just now.