The education of _______young is always _______ hot and serious topic in modern society.
—Why are you so depressed? —I _____ my MP4 player on the bus.
Tired and disappointed, the rescue team finally reached _____ used to be a village.
Noise is unpleasant, _____ when you are trying to sleep.
So hard-working _____ that he sets a good example to all the other classmates.
With more and more forests _____, many animals are facing the danger of dying out.