Everyone has a responsibility to save _____ water, if future generations are to enjoy a similar standard of living to _____ we enjoy now.
How can you expect to learn anything _____ you never listen?
---- Is everyone here? ----Not yet…Look, there _________ the rest of our guests.
One-third of the country ________ covered with trees and the majority of the citizens _______ black people.
Jane won’t join us for dinner tonight and ___________.
More and more high-rise buildings have been built in big cities________ space.