18.The old couple don’t know what to do with their son, who drinks___________every day.
. Driving a car without insurance can have _____ consequences.
. Probability is the mathematical study of the _____ of an event's occurrence.
. New mineral resources may be discovered during the forthcoming Antarctic _____.
They have been waiting for many hours to see the singer, but the airplane must have been _____.
Today, housework has been made much easier by electrical _____.