It was playing computer games that cost the boy plenty of time that he ______ spent doing his lessons.

Having heard my answer, the master nodded _______ satisfaction, “I’m quite satisfied _____you.”[ ]

If we don’t take steps. The Tibetan antelopes and pandas will_____ some day just as dinosaurs.

rld’s elderly population will exceed ____ of children by 2060, when each group____ to account for about one fifth of the population.

______! The rescue workers are coming.