People are starting to use energy from the sun, wind and water because they cost very________ and will never ________ .

Mr. Wang, a(n)_______editor and writer, isgoing to attend the conference to be held in Beijing next week.

hool is nolonger what it was 20 years ago, _______it was so poorly equipped

Prize winner Mo Yan said prizethe Academy had awarded to him was_______ victory of literature, but nota victory of politics

To make our city more beautiful, rubbish intothe river. —I agree.