---I wonder what makes you a good salesperson.---I _______ as a waiter for three years, which contributes a lot to my today’s work.A. serve B. have servedC served D. had served
Everything was perfect for the picnic ______ the weather.
Don’t promise anything ______ you are one hundred percent sure.
Dogs have a very good ______ of smell and are often used to search for survivors in an earthquake.
American Indianabout five percent of the U.S. population.
It is one of the funniest things ______ on the Internet so far this year.