Susan will not arrive at the airport on time _____she hurries up. A.once B.if C.unless
—Would you like some bread? —Yes, _________, please. Thank you.
—How much does it take to build the school library? — Four________ yuan.
You return the book now. You can keep it till next week.
Thank you for _______ the door for me.
I will have my hair _____ tomorrow.