[9급 지방직 영어 2015년 18번]

The 'ten-thousand-hour rule' states that expertise requires at least ten thousand hours of practice. Clearly, though, time is not the only requirement. Years of one's life spent practicing the wrong things will not lead to expertise any more than spending the same amount of time watching television. Time is a basic prerequisite, but not ____________________________________. Layered upon time are a slew of other ingredients, life focus, precision, discipline, and desire.