—People often don't appreciate what they have, do they? —No, _____ they lose it.
I’m going to be ___ basketball player.A.a B. the C. an
Either the guides or the team leader ________ looking after the students then.
When _______ comes to advertisements, we must all use our intelligence.
As they were walking around, they noticed a man _______ against a tree.
Today, when scientists examine mummies, they wear special clothing for protection _____ they breathe in harmful gas.