________ twice a year, whether it is a car or a bus or a truck, is the rule that every driver must obey in this city.
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.
Wow! That’s Uncle Sam. Now he’s in Paris, _____ he?
When _____ what is most important in life, some choose money, ____ others choose friendship.