---Will people use money ____ 100 years? ---No, they won’t. Everything will ____free.
He is _____ unusual writer. He can write _____ useful book.
---- I have very good grade in English this time . ---- _______________!
I didn’t understand my parents why they are so strict ______ me ______ my schoolwork.
Both red and black represent _____ . But I prefer to wear red when I feel tired .
He devoted all his time he had _____ others.