Complete the following sentences with the proper form of the words given in brackets. 1. ( acquire ) The army has gained greatly in fighting capacity with the ____ of 500 latest airplanes. 2. ( assume ) ____ that dieting is fruitless for people who think that they are too fat, the alternatives are fairly limited. 3. ( available ) Another reason why the increase in renting is likely to continue is its relationship to land prices and ____. 4. ( emerge ) Modern natural science came into being only after the ____ of experimental science. 5. ( explore ) Domestic oil ____ and gasoline prices are emerging as important issues in the presidential campaign. 6. ( overwhelm ) Recognizing the threat of the economic recession, the congress voted ____ last year to support economic reform measures. 7. ( virtual ) It used to be ____ impossible to find restaurants outside the cities, but it's much easier now. 8. ( assure ) The mayor gave ____ yesterday that there was no danger of any shortage of food as a result of the strike. 9. ( depart ) Online learning has marked a new ____ in education; now the students have more resources to turn to. 10. ( flexibility ) We need to set up a ____ employment system to provide more forms of employment. 11. ( incredible ) It is hardly ____ that she has grown so tall in just one year. 12. ( participate ) China is an active ____ in the international system and a builder, not a destroyer. 13. ( benefit ) Sporting and exercising are very ____ to you, as far as you don't do so long or so much. 14. ( stimulate ) Workers participation management is one basic system for modern enterprise management and an important method of ____ as well. 15. ( enthusiastic ) We're positive that this old city will continue to be one of the world's great cities in a new spirit of youthful ____.