构思和写作自传花费了那位美国作家三年多的时间,其间他遇到了许多无法想象的困难。

构思和写作自传花费了那位美国作家三年多的时间,其间他遇到了许多无法想象的困难。
【正确答案】：The process of thinking about and writing his autobiography took the American writer more than three years• during which he ran into many unimaginable difficulties.