They live in a beautiful village, with many trees and flowers _______ it.
It was announced that only when the terrible disease was under control _____ to return to their homes.
Spelling Bee is a contest _____ competitors, usually children, are asked to spell as many words as possible.
When asked to explain _____ he did to make his students so fascinated with his lessons, the teacher paused and thought deeply.
The subway was crowded with passengers going home from market, most of _____ carrying heavy bags and baskets full of fruit and vegetables they had bought there.
--- The research on the new flu virus vaccine is challenging and demanding. Who do you think can do the job? --- ____ my students have a try?