... ___47__ different. But after 80 training hours one person could recognize 18 of them, Studies of 76 major ___ 48_ ___ show that it took at least ten years of _____49______ training before any of them ... In one experiment, ten hours’ training _____43__ only a small __44__ but the results after practicing for a thousand hours were ___45__: some people remembered 80 or even 100 numbers. Similarly, ... 42.Repetition 43.Product 44.Improve 45.Amaze 46.Identify 47.Slight 48. Compose 49.Music 50.possible 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. D. Reading: I. Choose the best one that has the right order....